The 1.5 inch standard pump union is a universal pump union used for complete assembly of your replacement pump. Should fit any 1.5 inch end on most pumps.
3/8" x 1.5" Fender Washer used on the propulsion system in the swim spas. The 3/8" x 1.5" Fender Washer from Master Spa Parts has a thinner body compared to the flat washer and provides an even wider surface area of support for fasteners.