Stens 615-374 Carburetor Kit Replaces: Zama rib-40 Fits models: Zama: c1q-s33, a-b; c1q-s34, a-h; c1q-s35, a-b; c1q-s36, a-g; c1q-s51, a-c; c1q-sk4; c1q-sk5; c1q-sk6, a; Carburetors Ethanol: not compatible with greater than 10% ethanol fuel