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 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 symmetrical half-fitting with corrugated sleeve in AISI 316 stainless steel (1.4401) is the high-security transfer solution for corrosive and sensitive fluids. Compliant with NF E 29.572 standards, this 16 bar fitting offers exceptional resistance (50 bar burst) and unrivalled durability in...
The Guillemin symmetrical half-fitting with corrugated sleeve in AISI 316 stainless steel (1.4401) is the high-security transfer solution for corrosive and sensitive fluids. Compliant with NF E 29.572 standards, this 16 bar fitting offers exceptional resistance (50 bar burst) and unrivalled durability in...
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 symmetrical stainless steel cap with lock and chain is the ideal safety solution for hermetically closing your unused fittings. Made of robust stainless steel, it protects your networks from corrosion and impurities while preventing residual leaks. Its integrated chain prevents...
The Guillemin symmetrical stainless steel cap with lock and chain is the ideal safety solution for hermetically closing your unused fittings. Made of robust stainless steel, it protects your networks from corrosion and impurities while preventing residual leaks. Its integrated chain prevents...
The Guillemin symmetrical half-fitting with stainless steel weld-on lock is the ultimate solution for securing your connection points on fixed networks. Its weldable sleeve ensures a permanent structural seal, while its mechanical lock ensures a fast and robust coupling. Made of stainless steel...
The Guillemin symmetrical half-fitting with stainless steel weld-on lock is the ultimate solution for securing your connection points on fixed networks. Its weldable sleeve ensures a permanent structural seal, while its mechanical lock ensures a fast and robust coupling. Made of stainless steel...
The symmetrical Guillemin stainless steel reduction fitting with latches is the key part for adapting your pipe diameters safely. Made of heavy-duty stainless steel, it allows for a smooth transition between two nominal sizes while ensuring two-sided mechanical locking....
The symmetrical Guillemin stainless steel reduction fitting with latches is the key part for adapting your pipe diameters safely. Made of heavy-duty stainless steel, it allows for a smooth transition between two nominal sizes while ensuring two-sided mechanical locking....
The Guillemin symmetrical half-fitting with reduced corrugated bushing and AISI 316 stainless steel (CF8M) flange offers maximum safety for the transfer of aggressive fluids. Compliant with the NF E 29.572 and EN 14420-8 standards, it can withstand a working pressure of 16 bars and a burst at 50 bars. Ideal for...
The Guillemin symmetrical half-fitting with reduced corrugated bushing and AISI 316 stainless steel (CF8M) flange offers maximum safety for the transfer of aggressive fluids. Compliant with the NF E 29.572 and EN 14420-8 standards, it can withstand a working pressure of 16 bars and a burst at 50 bars. Ideal for...
The Guillemin symmetrical half-fitting without stainless steel weld lock is the ideal solution for creating fixed and durable connection points on your piping networks. Its weld-on bushing ensures a perfect structural seal, while its stainless steel construction guarantees maximum corrosion...
The Guillemin symmetrical half-fitting without stainless steel weld lock is the ideal solution for creating fixed and durable connection points on your piping networks. Its weld-on bushing ensures a perfect structural seal, while its stainless steel construction guarantees maximum corrosion...
The Guillemin symmetrical stainless steel irrigation-type flat plug is the ultimate safety solution for your outdoor installations. Its padlockable system protects your connection points from theft and vandalism, while its stainless steel construction...
The Guillemin symmetrical stainless steel irrigation-type flat plug is the ultimate safety solution for your outdoor installations. Its padlockable system protects your connection points from theft and vandalism, while its stainless steel construction...
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