BSP (British Standard Pipe) sizes refer to the nominal bore of the pipe, not the outer diameter of the thread. For example, a 1/2" BSP fitting typically has an outer thread diameter of approximately 20.9 mm (≈0.82"). Always measure the thread OD or check your existing fitting label. When in doubt, size up — a slightly larger connector is generally easier to seal than one that is too small.

Stainless steel BSP threaded fittings in these size ranges generally handle working pressures of up to 150 PSI (≈10 bar) in standard plumbing and fluid-transfer applications. Actual ratings depend on wall thickness, temperature, and the specific fluid. Contact us to confirm if your application involves elevated pressure or temperature.

Yes. Stainless steel offers strong resistance to rust, oxidation, and many chemicals, making these connectors well-suited for outdoor plumbing, marine environments, and light industrial use. For highly aggressive media (e.g., chlorinated water at elevated temperatures), verify the specific grade with us before ordering.

BSP and NPT threads are not directly interchangeable. BSP uses a 55° thread angle while NPT uses 60°. In some sizes the thread pitch is similar enough that they may appear to fit, but this typically results in leaks. Use a BSP-to-NPT adapter if you need to connect the two standards.

For a single connection point, 1 pc is sufficient. For a small plumbing project with multiple joints, ordering 4–10 pcs is generally more cost-effective and ensures you have spares on hand. Bulk packs of 20 pcs are ideal for contractors or workshop stock.

BSPP (parallel) threads require a sealant such as PTFE tape or thread compound to achieve a leak-free joint. BSPT (tapered) threads can self-seal under pressure but still benefit from PTFE tape for added security. We recommend applying 2–3 wraps of PTFE tape on all threaded connections.

Each numbered size (01# through 21#) corresponds to a specific BSP thread configuration — the label shows the male and female thread sizes involved (e.g., 01# covers 1" male to 1/2" female). Select the size that matches the two pipe ends you need to connect. If you are unsure, contact us with your pipe OD measurements and we will help you identify the correct size.