Waterway Executive spa pump barbed air bleed

Waterway Executive spa pump bleed nipple 
Threaded - screws into face of pump body in place of standard plug. 

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
6mm / 0.25" barb for connection to air bleed system.
0.25" MPT thread

Thread OD approx. 12mm x 10mm long