WD Fittings

WD Fittings Aeration » Air Diffuser Tubing » These black plastic fittings are required for the weighted diffuser tubing. The PIOU couples 1/2" tubing. The PIOM is a 1/2" male adapter. The tee union (PIOT) connects two lengths of tubing to a 1/2" MNPT male adapter. Tube insert supports included. Made in USA.