Waterway Spa Pump drain barb adaptor 1/4″ MPT x 3/8″ Barb

Pump drain bleed adaptor – 3/8″ / 9mm barb

The threaded end can be screwed into the drainage point on the wet end of most Waterway and Aqua-Flo pumps, among others, and this part is sometimes used to connect a small pipe to help prime the pump