The Stenner Pumps QuickPro® QP252-1 #2 Santoprene® Pump Head is a patent pending QuickPro® pump head that is easily identified by the collapsible roller assembly and latches securing the cover instead of screws. For quick service, replacing the pump head subassembly is a convenient option. The innermost pump head is the subassembly closest to the motor in the Classic Series double head fixed or adjustable pump