U-Shaped Drain Trap Internal External Thread

This U-shaped drain trap is fabricated from high-integrity plastic formulated for resistance to impact, creep, and environmental stress cracking. It incorporates UK-standard internal and external BSP threads — the internal thread mates with common 1½-inch sink waste spindles, while the external thread connects directly to 32 mm or 40 mm waste pipes. Its compact footprint suits narrow under-sink zones, and its smooth inner surface promotes laminar flow and inhibits biofilm adhesion. The U-bend geometry provides a stable, self-replenishing water seal each time the sink is used — automatically restoring barrier function without user intervention. This makes it especially suitable for households with variable usage patterns or seasonal occupancy. Fitting requires no specialist tools: hand-tightening achieves full seal integrity. To clean, separate the three components by unscrewing both ends — exposing the full interior surface of the U-section for inspection and de-scaling. No pipe cutting or adhesive removal is necessary, preserving existing plumbing integrity.