Not sure which fitting you need? Tell us what you have, we show you what screws onto it — live prices and stock.
Pipe thread chart: inch / mm conversion (BSP, 15/21, 20/27, S60x6)
A “1/2 inch” thread measures 20.96 mm, not 12.7: in plumbing, the inch size is not converted, it is read from a chart. Here you will find the inch / mm correspondence of every common thread (BSP or “gas thread”, French names 15/21 · 20/27 · 26/34, NPT, S60x6 IBC tanks, Guillemin, Camlock, PVC), a tool that identifies your thread and the fitting that goes with it, and the pitfalls to avoid.
Which thread do you have? Which fitting do you need?
No need to know the name of your thread. Tell us what you need to connect to, or type what you know (“20/27”, “3/4 inch”, “S60x6”, “26.4 mm”): we identify the thread and show you the fittings that go with it. Dimensions according to ISO 228, ISO 7 and ASME B1.20.1.
✔ Shipped next working day from our stock✔ 4.5/5 from more than 6,400 customer reviews✔ Not sure? Describe what you need, we will find the fitting with you⎙ Printable thread gauge (PDF, actual size)
No need to know the name of your thread. Just answer the question: what do you need to connect to?
With a caliper, measure the outside diameter of a male (thread visible on the outside) or the inside diameter of a female (thread inside the hole), at the root of the thread.
The Guillemin symmetrical cap with lock and aluminium chain is the optimal solution for sealing and protecting your connections. Made in France , this robust cap ensures a perfect seal thanks to its secure manual lock and its included NBR seal. Its integrated chain prevents any...
The Guillemin symmetrical cap with lock and aluminium chain is the optimal solution for sealing and protecting your connections. Made in France , this robust cap ensures a perfect seal thanks to its secure manual lock and its included NBR seal. Its integrated chain prevents any...
The simplified Guillemin symmetrical cap with aluminum handle and chain is the perfect accessory to protect your connection expectations. Made in France , this lockless model is easy to handle thanks to its ergonomic handle and always remains at hand thanks to its safety chain....
The simplified Guillemin symmetrical cap with aluminum handle and chain is the perfect accessory to protect your connection expectations. Made in France , this lockless model is easy to handle thanks to its ergonomic handle and always remains at hand thanks to its safety chain....
The lockable flat symmetrical Guillemin cap in aluminum is the essential safety accessory for your irrigation networks. Made in France , it allows you to lock access to your valves with a padlock, while remaining attached to the installation through its retention chain. Robust...
The lockable flat symmetrical Guillemin cap in aluminum is the essential safety accessory for your irrigation networks. Made in France , it allows you to lock access to your valves with a padlock, while remaining attached to the installation through its retention chain. Robust...
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