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 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 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...
Symmetric Guillemin half coupling with lock in polypropylene with male threaded socket. Designed for firefighting and industrial applications , this high-performance coupling integrates BSP gas threading for reliable and leak-proof connection. Perfect for suction and discharge of liquids,...
Symmetric Guillemin half coupling with lock in polypropylene with male threaded socket. Designed for firefighting and industrial applications , this high-performance coupling integrates BSP gas threading for reliable and leak-proof connection. Perfect for suction and discharge of liquids,...
The Guillemin Male Symmetrical Coupling with Stainless Steel Lock is the robust solution for your aggressive or powdery fluid transfers. Featuring a standard BSP thread, it is a perfect fit for pumps and stationary installations in the oil, chemical and pharmaceutical industries. Its stainless...
The Guillemin Male Symmetrical Coupling with Stainless Steel Lock is the robust solution for your aggressive or powdery fluid transfers. Featuring a standard BSP thread, it is a perfect fit for pumps and stationary installations in the oil, chemical and pharmaceutical industries. Its stainless...
The Guillemin Female Symmetrical Polypropylene Half Fitting with Lock provides exceptional chemical resistance for the transfer of aggressive fluids. Featuring a standard BSP tap, it easily adapts to your fixed installations while ensuring secure mechanical locking. Ideal for agriculture, water...
The Guillemin Female Symmetrical Polypropylene Half Fitting with Lock provides exceptional chemical resistance for the transfer of aggressive fluids. Featuring a standard BSP tap, it easily adapts to your fixed installations while ensuring secure mechanical locking. Ideal for agriculture, water...
The Guillemin Male Lockless Symmetrical Half Fitting made of 316 Stainless Steel is the ideal connection solution for demanding corrosive environments. Compliant with NF E 29.572 standards, this PN16 fitting with BSP thread can be installed on fixed equipment in the chemical, agri-food and oil...
The Guillemin Male Lockless Symmetrical Half Fitting made of 316 Stainless Steel is the ideal connection solution for demanding corrosive environments. Compliant with NF E 29.572 standards, this PN16 fitting with BSP thread can be installed on fixed equipment in the chemical, agri-food and oil...
The female lockless Guillemin symmetrical half coupling in 316 Stainless Steel is designed for demanding fluid transfers in corrosive environments. Compliant with NF E 29.572 and PN16 standards, this BSP threaded coupling guarantees maximum safety for the chemical, food processing and...
The female lockless Guillemin symmetrical half coupling in 316 Stainless Steel is designed for demanding fluid transfers in corrosive environments. Compliant with NF E 29.572 and PN16 standards, this BSP threaded coupling guarantees maximum safety for the chemical, food processing and...
The Guillemin Female Stainless Steel Symmetrical Half Coupling with Lock is the ideal quick-connect solution for the suction and discharge of various media. Its BSP thread allows for easy installation on your existing networks, while its stainless steel construction ensures optimal corrosion...
The Guillemin Female Stainless Steel Symmetrical Half Coupling with Lock is the ideal quick-connect solution for the suction and discharge of various media. Its BSP thread allows for easy installation on your existing networks, while its stainless steel construction ensures optimal corrosion...
The Guillemin symmetric half coupling with lock (Reference: 101338) in copper alloy offers a reliable and secure connection for professional applications. Fitted with a male BSP thread , this coupling is designed to withstand the stresses of suction and discharge in demanding industrial environments. Ideal for fire...
The Guillemin symmetric half coupling with lock (Reference: 101338) in copper alloy offers a reliable and secure connection for professional applications. Fitted with a male BSP thread , this coupling is designed to withstand the stresses of suction and discharge in demanding industrial environments. Ideal for fire...
The male Guillemin symmetrical half coupling in aluminium with lock (without jaws) is the ideal unloading solution for bulk transport and high-tech industries. Made in France with a standard BSP thread, it enables powerful and secure mechanical locking. Its lightness and...
The male Guillemin symmetrical half coupling in aluminium with lock (without jaws) is the ideal unloading solution for bulk transport and high-tech industries. Made in France with a standard BSP thread, it enables powerful and secure mechanical locking. Its lightness and...
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