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 half coupling with reduced corrugated sleeve and collar is the reference solution for secure crimping on technical hoses. Manufactured in France from high-strength aluminium (T6), it complies with NF E 29.572 and EN 14420-8 standards. Capable of withstanding a service...
The Guillemin symmetrical half coupling with reduced corrugated sleeve and collar is the reference solution for secure crimping on technical hoses. Manufactured in France from high-strength aluminium (T6), it complies with NF E 29.572 and EN 14420-8 standards. Capable of withstanding a service...
The Guillemin symmetric half-coupling with annulated shank in aluminium is the professional solution for crimping technical flexible hoses. Made in France , this "fire hose" coupling is compatible with suction and discharge for various fields such as firefighting, petrochemical industry and...
The Guillemin symmetric half-coupling with annulated shank in aluminium is the professional solution for crimping technical flexible hoses. Made in France , this "fire hose" coupling is compatible with suction and discharge for various fields such as firefighting, petrochemical industry and...
The male Guillemin symmetric half coupling in aluminium with lock is the ideal quick-connect solution for your industrial and agricultural installations. Made in France with a standard BSP thread, it enables secure mechanical locking thanks to its movable jaws. Suitable for...
The male Guillemin symmetric half coupling in aluminium with lock is the ideal quick-connect solution for your industrial and agricultural installations. Made in France with a standard BSP thread, it enables secure mechanical locking thanks to its movable jaws. Suitable for...
The Guillemin Female Symmetrical Half-Fitting without Lock (without jaws) is the ideal solution for your tapped fixed equipment. Made in France with a standard BSP thread, it allows a quick and hermetic connection with any coupling with a lock. Versatile and robust, it is indispensable for...
The Guillemin Female Symmetrical Half-Fitting without Lock (without jaws) is the ideal solution for your tapped fixed equipment. Made in France with a standard BSP thread, it allows a quick and hermetic connection with any coupling with a lock. Versatile and robust, it is indispensable for...
The symmetrical Guillemin reducing coupling with locks in aluminum is the perfect solution for safely adapting your pipe diameters. Made in France , this robust coupling enables watertight transition between two hose or valve sizes thanks to its 360° double locking system....
The symmetrical Guillemin reducing coupling with locks in aluminum is the perfect solution for safely adapting your pipe diameters. Made in France , this robust coupling enables watertight transition between two hose or valve sizes thanks to its 360° double locking system....
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 male Guillemin symmetrical half coupling without lock in aluminium is the ideal component for equipping the fixed outlets of pumps or manifolds. Fitted with a BSP (British Standard Pipe) thread and manufactured in France, it ensures a quick and secure connection with any coupling fitted with a lock. Versatile and...
The male Guillemin symmetrical half coupling without lock in aluminium is the ideal component for equipping the fixed outlets of pumps or manifolds. Fitted with a BSP (British Standard Pipe) thread and manufactured in France, it ensures a quick and secure connection with any coupling fitted with a lock. Versatile and...
The female symmetrical Guillemin half coupling in aluminium with lock is the reference equipment for a secure and lightweight connection. Made in France with a standard BSP thread, it enables reliable mechanical locking thanks to its movable jaws. Versatile and robust, it is...
The female symmetrical Guillemin half coupling in aluminium with lock is the reference equipment for a secure and lightweight connection. Made in France with a standard BSP thread, it enables reliable mechanical locking thanks to its movable jaws. Versatile and robust, it is...
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...
The Guillemin grooved socket aluminium half-coupling is designed for robust assembly with segmented clamps. Made in France to NF E 29.572 standards, it supports a working pressure of 16 bar. Ideal for petroleum, chemical and agricultural sectors, this AS7G T6-treated aluminium coupling ensures...
The Guillemin grooved socket aluminium half-coupling is designed for robust assembly with segmented clamps. Made in France to NF E 29.572 standards, it supports a working pressure of 16 bar. Ideal for petroleum, chemical and agricultural sectors, this AS7G T6-treated aluminium coupling ensures...
The Guillemin symmetrical half-coupling without jaws in aluminium is the ideal crimping accessory for your technical hoses. Made in France , this lightweight and robust coupling is designed to fit perfectly with locking models, both in suction and discharge. Compatible with drawn skirts and...
The Guillemin symmetrical half-coupling without jaws in aluminium is the ideal crimping accessory for your technical hoses. Made in France , this lightweight and robust coupling is designed to fit perfectly with locking models, both in suction and discharge. Compatible with drawn skirts and...
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