Air relief plug with o ring. Used on Dimension 1 Spas
**This part is now discontinued. We have only a few of these left in stock.
Diameter : 58mm Part is now white plastic.
Larger version of the 600-1040. The 600-1020 is ONLY for the Dyna Flo XL filter assembly. Diameter : 68mm
Item number 2 from the exploded diagram.