Sierra 18-9845 Seal Driver - Replaces Mercury 91-43591T Installs upper drive shaft oil seal on Alpha One and Alpha OneGen II drive units. Interchangeable with Mercury Marine 91-43591T California Residents WARNING Cancer and Reproductive Harm - P65Warnings.ca.gov Other Details Google Product Type Special Tools Wiser Yes Product MPN 18-9845 Product UPC 808282109530 Fast Ship In Stock Ships Today