Male Straight Adapter 1/4" Tube x 1/4" BSPT - DMfit

Straight adapter 1/4" tube × 1/4" BSPT

The AAMCBT 0404 connects 1/4" semi-rigid tubing to a 1/4" BSP female thread. On the tube side, a push-fit connection: the tube is pushed fully home, the collet locks it and the O-ring seals it. On the thread side, a 1/4" BSPT male.

BSPT: a tapered thread

BSPT (British Standard Pipe Taper, ISO 7/1) is a tapered thread. Unlike a parallel thread that seals on a flat face or a gasket, BSPT seals on the threads themselves: the taper wedges into the female port and tightening creates the contact.

Two consequences. Sealant is always required, PTFE tape or pipe sealant, applied in the direction of tightening. And do not overtighten: on a polymer port the taper acts as a wedge and can split the receiving thread. Hand-tight plus a quarter turn with a spanner is enough in most cases.

Do not confuse with NPTF

BSPT is the European standard, NPTF the American one. Both are tapered, but thread angle and pitch differ (55° against 60°). They are not interchangeable: a BSPT male in an NPTF port engages only a few threads and will eventually leak or strip. Always check the standard of the receiving port before ordering.

Where to use it

On domestic and professional reverse osmosis systems, filter housings and filter heads with BSP ports, valves, pressure gauges and solenoid valves, and anywhere a threaded port has to feed a 1/4" tubing run.

Montage

Cut the tube square and clean, an angled or crushed cut compromises the O-ring seal. Push in until it bottoms out, then pull lightly to check engagement. To disconnect: push the collet towards the fitting body while pulling the tube out.