BSP Brass Tee Pipe Fittings — Male & Female Thread Combinations, 1/8" to 3/8"

Measure the outer diameter of your pipe threads and match to the nominal BSP size. As a general guide: 1/8" BSP is typically used for small instrumentation or gas pilot lines, 1/4" for light-duty water or air distribution, and 3/8" for moderate-flow plumbing runs. When in doubt, use a thread gauge or caliper — nominal BSP sizes do not directly equal the measured thread OD. For example, a 1/4" BSP thread typically measures around 13.16mm (≈0.518") OD.

A Male (M) port has external threads that screw into a female-threaded socket, valve, or body. A Female (F) port has internal threads that accept a male-threaded pipe nipple or fitting. Each execution listed (e.g., Tee M&M&F) describes the thread gender of the three ports in order: run port 1 — run port 2 — branch port. Choose the configuration that matches what your existing pipes or valves present at each connection point.

Brass fittings generally offer good tensile strength suitable for residential and light commercial plumbing, compressed air systems, and moderate-pressure hydraulic lines. Exact working pressure ratings depend on the specific port size and wall thickness of each fitting. For applications with defined pressure requirements, contact us to confirm the rating for your chosen size before ordering.

Brass is naturally corrosion-resistant and typically performs well in outdoor, humid, or wet environments — making it a common choice for garden irrigation tee fittings and exterior plumbing connections. It is generally not recommended for prolonged direct contact with seawater or highly acidic/alkaline fluids without additional protection. Applying PTFE thread tape during installation helps ensure a watertight, weather-resistant seal.

No — BSP and NPT are different thread standards and are not directly interchangeable. BSP threads have a 55° thread angle, while NPT uses 60°; pitch and OD dimensions also differ. If your existing system uses NPT fittings, you will need a BSP-to-NPT adapter. Always verify the thread standard of your existing pipes and valves before ordering to avoid mismatches.

Choose based on what your existing pipe ends or valve ports present at each of the three connection points. If all three connection points on your system have female-threaded sockets (internal threads), select a Tee M&M&M (all external/male ports). If all three points have male-threaded nipples (external threads), select a Tee F&F&F (all internal/female ports). For mixed situations — for example, two female sockets on the run and a male nipple on the branch — choose the corresponding mixed configuration such as Tee M&M&F.

Yes, PTFE (Teflon) thread tape or a suitable pipe thread sealant compound is generally recommended for BSP connections to achieve a reliable, leak-free seal — especially for water and compressed air lines. BSPT (tapered) threads can sometimes seal on the taper alone, but sealant is still advisable in most plumbing applications. Wrap PTFE tape clockwise (when facing the male thread end) for 2–3 turns before assembly.

A reducing tee has different port sizes across its three connections — for example, a 3/8"×3/8"×1/2" tee has a larger branch port than the run ports. This is used when your main line runs at one diameter but the branch line requires a different size, such as tapping a 1/2" supply into a 3/8" run. Select the size variant that matches your specific run and branch pipe diameters.