Sierra's 18-2946 Head Gasket fits GM 181 (3.0L) CID engines. It interchangeable with Chris-Craft 16.50-00204, GLM 36150, Mallory 9-63700, Mercruiser Stern Drive 27-52364, 27-810841, FI5000204, OMC Stern Drive 0914812, 3853336, 908611, 913274, and Volvo Penta 3853336, 908611. Each Sierra product meets or exceeds the original equipment part it replaces.