Solas SR-CD-12/20 Concord Sea Doo impeller has unique blade design that delivers remarkable thrust take off, improves acceleration and top speed 2+mph. Solas sr-cd-12/20 seadoo impeller is great for pulling skiers to racing... Solas sr-cd-20/12 This upgrade over stock Sea Doo Impeller fits: GTX 4-tec Ltd. SC 03-04,GTX 4-tec SC 185 03-06