B.S.P.T.

British Standard Pipe Thread


British Standard Pipe Thread is a family of standard screw thread types that has been adopted internationally for interconnecting and sealing pipe ends by mating an external (male) with an internal (female) thread.


A list of 16 thread sizes are defined by the standards, ranging from 1⁄16 Inch to 6 Inch. The size was originally based on the inner diameter measured in inches of a steel tube for which the thread was intended. This often causes confusion, as people think the size refers to the outside diameter of the male thread.

Two types of threads are used:

Parallel (straight) threads, British Standard Pipe Parallel thread (BSPP)

Taper threads, British Standard Pipe Taper thread (BSPT)

Just to confuse things, often the T in BSPT refers to Thread and doesn't indicate either Taper or Parallel.

The threadform follows the British Standard Whitworth standard


The table below shows dimensions for male threads.


Thread

Threads per inch

Pitch mm

Outside Diameter mm

Outside Diameter inches

1/16 Inch

28

0.907

7.723

0.304

1/8 Inch

28

0.907

9.728

0.383

1/4 Inch

19

1.337

13.157

0.518

3/8 Inch

19

1.337

16.662

0.656

1/2 Inch

14

1.814

20.995

0.825

5/8 Inch

14

1.814

22.991

0.902

3/4 Inch

14

1.814

26.441

1.041

1 Inch

11

2.309

33.249

1.309

1¼ Inch

11

2.309

41.910

1.650

1½ Inch

11

2.309

47.803

1.882

2 Inch

11

2.309

59.614

2.347

2½ Inch

11

2.309

75.184

2.96

3 Inch

11

2.309

87.884

3.46

4 Inch

11

2.309

113.030

4.45

5 Inch

11

2.309

138.430

5.45

6 Inch

11

2.309

163.830

6.45


This is a 1/2 Inch thread, you can count 14 threads in one inch.


An end view of a 1/2 Inch male thread



As the name of the sizing does not match the actual diameter, there can be some confusion over sizing. We have shown some pictures of two of the more popular sizes along side popular UK coins.

First, a half inch thread which is similar in size to a 1 penny coin.



Second, a three quarter inch thread which is similar in size to a 2 pence coin :


Typical uses and sizes are :

1/4 Inch - Compressed air connections

3/8 Inch - Oil line connections

1/2 Inch - Basin and sink taps, radiator inlets, old outside tap outlets

5/8 Inch - Old outside tap outlets (very rare)

3/4 Inch - Bath taps, washing machine inlet hose connections, modern outside tap outlets

1 Inch Domestic heating boilers

1.25 Inch - Wash hand basin wastes (bathroom sink)

1.5 Inch - Kitchen sink wastes (kitchen sink), bath wastes, WC syphon outlets

2 Inch - Modern toilet flushvalve outlets


A selection of "Black Iron" BSPT fittings :

BSPT fittings


A selection of plumbing fittings with BSP threads : spesonline


1 Inch BSP Brass Backnut (British Standard Pipe Thread)
2.10
End date: Friday Aug-22-2014 12:25:53 BST
Buy it now for only: £2.10
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3/8 Inch BSP Brass Blanking Plugs (2 Pack)
2.50
End date: Monday Aug-25-2014 13:15:27 BST
Buy it now for only: £2.50
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1/2 Inch BSP Radiator Tails. Radiator Valve Connecting Pieces (Pack of 2)
2.99
End date: Friday Aug-15-2014 10:26:28 BST
Buy it now for only: £2.99
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1 Inch BSP Brass Gate Valve
6.40
End date: Saturday Aug-16-2014 12:44:44 BST
Buy it now for only: £6.40
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3/8 Inch BSP Brass Threaded Female x Female Elbow / Bend (F x F)
2.46
End date: Thursday Aug-14-2014 19:00:52 BST
Buy it now for only: £2.46
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1/4 Inch Brass Flanged Plugs | ? BSP | British Standard Pipe Thread | 2 Pack
2.52
End date: Monday Aug-25-2014 13:17:47 BST
Buy it now for only: £2.52
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3/8 Inch BSP Alloy Central Heating Oil Filter
5.57
End date: Wednesday Aug-20-2014 9:04:24 BST
Buy it now for only: £5.57
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6 Bar 1/2 Inch BSP Safety Valve / Water Pressure Relief Valve
6.03
End date: Monday Aug-25-2014 13:22:56 BST
Buy it now for only: £6.03
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15mm x 3/4 Inch Male BSP Compression Coupler / Connector
2.95
End date: Friday Aug-15-2014 10:26:30 BST
Buy it now for only: £2.95
Buy it now  |  Add to watch list

1/2 Inch BSP Male x 15mm Compression Straight Connector / Coupler
2.99
End date: Monday Aug-25-2014 22:00:15 BST
Buy it now for only: £2.99
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1/2 Inch BSP Brass Plug (British Standard Pipe Thread)
1.93
End date: Monday Aug-25-2014 13:17:52 BST
Buy it now for only: £1.93
Buy it now  |  Add to watch list

22mm x 1 Inch Male BSP Compression Elbow / Bend
4.35
End date: Monday Aug-25-2014 13:17:45 BST
Buy it now for only: £4.35
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20 Pack Plastic 3/4" BSP x 1/2" BSP Reducing Bushes With Washers
2.49
End date: Monday Aug-11-2014 16:04:28 BST
Buy it now for only: £2.49
Buy it now  |  Add to watch list

3/4 Inch BSP Brass Threaded Female x Female Elbow / Bend (F x F)
5.36
End date: Thursday Jul-31-2014 18:31:46 BST
Buy it now for only: £5.36
Buy it now  |  Add to watch list

1/4 Inch Brass Male x Female Elbow | ? BSP M x F
2.50
End date: Wednesday Aug-20-2014 9:04:21 BST
Buy it now for only: £2.50
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10mm x 1/4 Inch Male BSP Compression Coupler / Adaptor
1.80
End date: Monday Aug-04-2014 16:02:05 BST
Buy it now for only: £1.80
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Braided Flexible Heating Oil Line Hose 1/4 Inch BSP Female x 1/4 Inch BSP Female
10.52
End date: Saturday Aug-02-2014 16:59:07 BST
Buy it now for only: £10.52
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1/2? Brass Flanged Back-Nuts | ? BSP | British Standard Pipe Thread | Pack of 2
2.10
End date: Tuesday Aug-26-2014 16:52:25 BST
Buy it now for only: £2.10
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22mm x 1 Inch Female BSP Compression Coupler / Connector
4.12
End date: Monday Aug-25-2014 13:20:32 BST
Buy it now for only: £4.12
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1 1/4 Inch BSP Brass Back Nut (British Standard Pipe Thread)
3.19
End date: Sunday Aug-17-2014 17:33:15 BST
Buy it now for only: £3.19
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1/8 Inch BSP Brass Plugs British Standard Pipe Thread (2 Pack)
2.54
End date: Friday Aug-15-2014 10:21:18 BST
Buy it now for only: £2.54
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15mm x 1/2 Inch Female BSP Compression Coupler / Connector
2.13
End date: Wednesday Aug-20-2014 9:11:35 BST
Buy it now for only: £2.13
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3/4 x 3/4 x 1/2 Inch Black Iron Tee | ? X ? X ? BSP
1.10
End date: Sunday Aug-24-2014 18:48:48 BST
Buy it now for only: £1.10
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1/2 Inch BSP Brass Blanking Cap (British Standard Pipe Thread)
1.23
End date: Friday Aug-15-2014 10:15:11 BST
Buy it now for only: £1.23
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MDPE / Poly 32mm Pipe x 1 Inch BSP Philmac End Connector
5.99
End date: Sunday Aug-10-2014 8:48:08 BST
Buy it now for only: £5.99
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3/4 Inch BSP Brass Swing Check / One Way Valve
6.66
End date: Tuesday Aug-19-2014 12:56:28 BST
Buy it now for only: £6.66
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10mm x 1/2 Inch Female BSP Compression Coupler / Connector
2.26
End date: Friday Aug-22-2014 22:16:46 BST
Buy it now for only: £2.26
Buy it now  |  Add to watch list

3/8 Inch BSP Brass Gate Valve. Water Valve With Red Handle.
6.65
End date: Thursday Aug-21-2014 11:27:34 BST
Buy it now for only: £6.65
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1/2 Inch BSP Chrome Plated Brass Cap (British Standard Pipe Thread)
2.84
End date: Saturday Aug-09-2014 12:59:15 BST
Buy it now for only: £2.84
Buy it now  |  Add to watch list

1/2 Inch BSP Brass Socket / Coupler (British Standard Pipe Thread)
2.01
End date: Saturday Aug-02-2014 15:57:54 BST
Buy it now for only: £2.01
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1/4 Inch Brass Female x Female Elbow | ? BSP F x F
2.99
End date: Friday Aug-15-2014 10:15:21 BST
Buy it now for only: £2.99
Buy it now  |  Add to watch list

3 Bar Boiler Pressure Relief Safety Valve. 1/2 Inch BSP Female x Female
5.55
End date: Friday Aug-15-2014 10:13:17 BST
Buy it now for only: £5.55
Buy it now  |  Add to watch list

1/2 Inch BSP Brass Gate Valve
3.52
End date: Wednesday Jul-30-2014 11:37:05 BST
Buy it now for only: £3.52
Buy it now  |  Add to watch list

3/4 Inch BSP Inline Brass Filter With Stainless Element
6.01
End date: Saturday Aug-02-2014 16:45:49 BST
Buy it now for only: £6.01
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15mm Copper x 1/2 Inch Female BSP Chrome Plated Compression Connector / Coupler
2.60
End date: Monday Aug-25-2014 18:09:18 BST
Buy it now for only: £2.60
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8mm x 1/4 Inch Male BSP Compression Elbow / Bend
1.38
End date: Wednesday Aug-20-2014 9:11:38 BST
Buy it now for only: £1.38
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American Fridge Freezer Quarter Inch Pipe x 3/4 Inch BSP Coupler
3.78
End date: Thursday Aug-14-2014 23:25:29 BST
Buy it now for only: £3.78
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3/4? Brass Blanking Cap and Washer | ? BSP | British Standard Pipe Thread
1.99
End date: Thursday Aug-14-2014 9:08:58 BST
Buy it now for only: £1.99
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10mm x 1/4 Inch Female BSP Compression Female Coupler / Connector
1.73
End date: Wednesday Aug-20-2014 9:11:30 BST
Buy it now for only: £1.73
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3/4 Inch x 1/2 Inch Brass Hex Bush | BSP - British Standard Pipe Thread
1.37
End date: Wednesday Aug-06-2014 11:48:26 BST
Buy it now for only: £1.37
Buy it now  |  Add to watch list

1 Inch BSP Brass Threaded Male x Female Elbow / Bend (M x F)
7.36
End date: Thursday Aug-14-2014 17:21:14 BST
Buy it now for only: £7.36
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1/2 Inch BSP Galvanised Iron Tee (British Standard Pipe Thread)
1.78
End date: Monday Aug-25-2014 18:33:18 BST
Buy it now for only: £1.78
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1 1/4 Inch BSP Brass Cap (British Standard Pipe Thread)
3.96
End date: Saturday Aug-23-2014 10:32:21 BST
Buy it now for only: £3.96
Buy it now  |  Add to watch list

1/4 Inch BSP x 6mm Compression Male Straight Connector / Coupler
1.97
End date: Thursday Aug-07-2014 11:00:40 BST
Buy it now for only: £1.97
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1/4 Inch x 1/4 Inch BSP Oil Line Nipple - Conical Faces
2.42
End date: Monday Aug-25-2014 10:10:40 BST
Buy it now for only: £2.42
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3/8 Inch Brass Male x Female Elbow | 3/8? BSP M x F
2.80
End date: Sunday Aug-10-2014 8:48:29 BST
Buy it now for only: £2.80
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Rubber Plumbing Heating 1/2" BSP Washers. 22mm Internal Diameter (10 Pack )
2.20
End date: Sunday Aug-17-2014 14:14:56 BST
Buy it now for only: £2.20
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10mm x 3/8 Inch Male BSP Compression Elbow / Bend
1.84
End date: Monday Aug-25-2014 21:01:41 BST
Buy it now for only: £1.84
Buy it now  |  Add to watch list

3/4 Inch BSP Malleable Black Iron Elbow / Bend. Female x Female FXF
1.88
End date: Monday Aug-11-2014 0:10:49 BST
Buy it now for only: £1.88
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28mm x 1 Inch Male BSP Compression Coupler / Connector
3.90
End date: Friday Aug-22-2014 22:21:15 BST
Buy it now for only: £3.90
Buy it now  |  Add to watch list

28mm x 1 Inch Female BSP Compression Coupler / Connector
4.42
End date: Friday Aug-22-2014 22:16:39 BST
Buy it now for only: £4.42
Buy it now  |  Add to watch list

3/4 Inch BSP Brass Gate Valve
3.88
End date: Saturday Aug-16-2014 13:37:49 BST
Buy it now for only: £3.88
Buy it now  |  Add to watch list

3/4 Inch x 150mm Long BSP Mild Steel Barrel Nipple
3.50
End date: Wednesday Aug-13-2014 18:21:28 BST
Buy it now for only: £3.50
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1/8 Inch Brass Socket / Coupler | BSP - British Standard Pipe Thread
1.00
End date: Wednesday Jul-30-2014 11:01:14 BST
Buy it now for only: £1.00
Buy it now  |  Add to watch list

1/4 Inch BSP Brass Equal Tee Fitting (British Standard Pipe Thread)
3.91
End date: Sunday Aug-10-2014 8:43:44 BST
Buy it now for only: £3.91
Buy it now  |  Add to watch list

3/4 Inch BSP Brass Socket / Coupler (British Standard Pipe Thread)
2.39
End date: Tuesday Aug-19-2014 12:14:38 BST
Buy it now for only: £2.39
Buy it now  |  Add to watch list

1/2 Inch BSP Low Pressure BS1212 Brass Float Valve / Ballcock
10.74
End date: Monday Aug-25-2014 18:33:15 BST
Buy it now for only: £10.74
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1/2 Inch BSP Malleable Black Iron Plug (British Standard Pipe Thread)
2.10
End date: Monday Aug-25-2014 19:56:34 BST
Buy it now for only: £2.10
Buy it now  |  Add to watch list

3/4 Inch Brass Flanged Plug | BSP - British Standard Pipe Thread
2.31
End date: Tuesday Aug-12-2014 13:02:57 BST
Buy it now for only: £2.31
Buy it now  |  Add to watch list

8mm x 1/4 Inch Female BSP Compression Elbow / Bend
1.96
End date: Monday Aug-25-2014 22:11:52 BST
Buy it now for only: £1.96
Buy it now  |  Add to watch list

15mm x 1/2 Inch Male BSP Chrome Plated Male Coupler / Connector
2.60
End date: Friday Aug-22-2014 22:18:37 BST
Buy it now for only: £2.60
Buy it now  |  Add to watch list

15mm Compression Tee With 1/2 Inch Female BSP Branch. Useful For Drain Or Vent
2.76
End date: Monday Aug-18-2014 10:53:16 BST
Buy it now for only: £2.76
Buy it now  |  Add to watch list

3/4 Inch x 150mm BSP Barrel Nipple Mild Steel
5.35
End date: Thursday Aug-14-2014 17:16:29 BST
Buy it now for only: £5.35
Buy it now  |  Add to watch list

22mm x 1 Inch BSP Male Compression Coupler / Connection
4.42
End date: Saturday Aug-23-2014 0:04:10 BST
Buy it now for only: £4.42
Buy it now  |  Add to watch list

1/2 Inch x 1/8 Inch Brass Hex Bush | BSP - British Standard Pipe Thread
1.00
End date: Thursday Jul-31-2014 17:05:04 BST
Buy it now for only: £1.00
Buy it now  |  Add to watch list

1/2 Inch BSP Brass Threaded Male x Female Elbow / Bend (M x F)
3.94
End date: Thursday Aug-21-2014 10:45:06 BST
Buy it now for only: £3.94
Buy it now  |  Add to watch list

3/4 Inch BSP Brass Threaded Male x Female Elbow / Bend (M x F)
6.71
End date: Friday Aug-01-2014 8:39:20 BST
Buy it now for only: £6.71
Buy it now  |  Add to watch list

1/2 Inch BSP Brass Threaded Female x Female Elbow / Bend ( F x F)
4.03
End date: Monday Aug-11-2014 14:21:00 BST
Buy it now for only: £4.03
Buy it now  |  Add to watch list

1 Inch Brass Flanged Plug | BSP - British Standard Pipe Thread
3.04
End date: Monday Aug-25-2014 19:49:18 BST
Buy it now for only: £3.04
Buy it now  |  Add to watch list

1 1/2 Inch Brass Flanged Plug | BSP - British Standard Pipe Thread
6.68
End date: Monday Aug-11-2014 14:46:33 BST
Buy it now for only: £6.68
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1/2 Inch BSP Crane D138 PN25 Bronze Swing Check / One Way Valve
9.99
End date: Friday Aug-08-2014 18:05:32 BST
Buy it now for only: £9.99
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Chrome Plated Hex Bush 3/4 Inch x 1/2 Inch BSP
3.69
End date: Tuesday Aug-12-2014 18:03:44 BST
Buy it now for only: £3.69
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10mm x 3/8 Inch BSP Male Compression Coupler / Connection
1.76
End date: Saturday Aug-09-2014 12:25:12 BST
Buy it now for only: £1.76
Buy it now  |  Add to watch list

Brass Hex Nipple 1/4 Inch x 1/8 Inch BSP (British Standard Pipe Thread)
3.20
End date: Monday Aug-25-2014 18:26:36 BST
Buy it now for only: £3.20
Buy it now  |  Add to watch list

3/4 Inch x 1/4 Inch Brass Hex Bush | BSP - British Standard Pipe Thread
2.19
End date: Wednesday Aug-20-2014 9:11:32 BST
Buy it now for only: £2.19
Buy it now  |  Add to watch list

1 Inch Brass Blanking Cap | BSP - British Standard Pipe Thread
2.94
End date: Saturday Aug-02-2014 16:59:21 BST
Buy it now for only: £2.94
Buy it now  |  Add to watch list

1/4 Inch BSP Brass Socket / Coupler (British Standard Pipe Thread)
1.51
End date: Monday Aug-11-2014 16:41:11 BST
Buy it now for only: £1.51
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1/2 Inch x 1/4 Inch Brass Hex Bush | BSP - British Standard Pipe Thread
1.32
End date: Saturday Aug-02-2014 16:57:40 BST
Buy it now for only: £1.32
Buy it now  |  Add to watch list

1/2 Inch BSP Drain Cock Valve With Leakproof Gland (Type A)
2.72
End date: Saturday Aug-23-2014 10:50:10 BST
Buy it now for only: £2.72
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1/4 Inch Brass Hex Nipple | BSP - British Standard Pipe Thread
1.34
End date: Sunday Aug-17-2014 17:37:05 BST
Buy it now for only: £1.34
Buy it now  |  Add to watch list

8mm x 1/4 Inch Female BSP Compression Coupler / Connector
2.38
End date: Monday Aug-25-2014 22:11:56 BST
Buy it now for only: £2.38
Buy it now  |  Add to watch list

1 Inch BSP Brass Socket / Coupler (British Standard Pipe Thread)
3.98
End date: Saturday Aug-02-2014 14:57:20 BST
Buy it now for only: £3.98
Buy it now  |  Add to watch list

22mm x 3/4 Inch Female BSP Compression Coupler / Connector
2.84
End date: Monday Aug-25-2014 21:45:17 BST
Buy it now for only: £2.84
Buy it now  |  Add to watch list

1 1/4 Inch Brass Flanged Plug | BSP - British Standard Pipe Thread
3.36
End date: Saturday Aug-16-2014 23:55:18 BST
Buy it now for only: £3.36
Buy it now  |  Add to watch list

15mm x 1/2 Inch Female BSP Compression Elbow / Bend
2.27
End date: Monday Aug-25-2014 21:54:37 BST
Buy it now for only: £2.27
Buy it now  |  Add to watch list

1 Inch BSP Brass Threaded Female x Female Elbow / Bend ( F x F)
6.45
End date: Saturday Aug-16-2014 12:05:28 BST
Buy it now for only: £6.45
Buy it now  |  Add to watch list

1/2 Inch BSP Inline Brass Filter / Strainer. With Stainless Steel Element.
3.46
End date: Monday Aug-04-2014 15:42:01 BST
Buy it now for only: £3.46
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2 Inch Brass Flanged Plug | BSP - British Standard Pipe Thread
8.19
End date: Monday Aug-25-2014 21:07:22 BST
Buy it now for only: £8.19
Buy it now  |  Add to watch list

22mm x 3/4 Inch Male BSP Compression Coupler / Connector
2.22
End date: Monday Aug-25-2014 21:43:44 BST
Buy it now for only: £2.22
Buy it now  |  Add to watch list

Automatic Air Vent (Bottle Type) 1/2 Inch BSP
4.67
End date: Friday Aug-01-2014 14:42:32 BST
Buy it now for only: £4.67
Buy it now  |  Add to watch list

3/8 Inch BSP Female x 15mm Compression Flexible Tap Connector Hose
2.80
End date: Monday Aug-25-2014 22:18:15 BST
Buy it now for only: £2.80
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1/2 Inch x 3/8 Inch Brass Hex Bush | BSP - British Standard Pipe Thread
1.00
End date: Friday Aug-08-2014 16:04:23 BST
Buy it now for only: £1.00
Buy it now  |  Add to watch list

1/2 Inch BSP Malleable Black Iron Equal Tee (British Standard Pipe Thread)
1.88
End date: Tuesday Jul-29-2014 14:42:05 BST
Buy it now for only: £1.88
Buy it now  |  Add to watch list

15mm x 3/4 Inch Female BSP Compression Coupler / Connector
3.17
End date: Thursday Aug-14-2014 21:55:34 BST
Buy it now for only: £3.17
Buy it now  |  Add to watch list

1/4 Inch BSP Brass Cap (British Standard Pipe Thread)
1.20
End date: Saturday Aug-09-2014 12:06:12 BST
Buy it now for only: £1.20
Buy it now  |  Add to watch list

3/8 Inch BSP Brass Socket / Coupler (British Standard Pipe Thread)
1.64
End date: Saturday Aug-02-2014 12:50:31 BST
Buy it now for only: £1.64
Buy it now  |  Add to watch list

10mm x 3/8 Inch Female BSP Compression Elbow / Bend
2.11
End date: Monday Aug-25-2014 21:01:48 BST
Buy it now for only: £2.11
Buy it now  |  Add to watch list

3/8 Inch BSP Brass Cap (British Standard Pipe Thread)
1.26
End date: Thursday Jul-31-2014 11:54:18 BST
Buy it now for only: £1.26
Buy it now  |  Add to watch list

15mm x 12mm Compression Reducing Coupler / Connector. With 3/8 Inch BSP Feature
3.16
End date: Sunday Aug-17-2014 11:39:09 BST
Buy it now for only: £3.16
Buy it now  |  Add to watch list

1/2 Inch BSP Brass Equal Tee Fitting (British Standard Pipe Thread)
5.23
End date: Thursday Aug-07-2014 10:29:30 BST
Buy it now for only: £5.23
Buy it now  |  Add to watch list


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