621 Series Alternator - Spindle Mount(Single Foot) - 100A - 12VFeatures:. 100A. 12V. Spindle Mount (Single Foot). 1-2". Single Deep Vee Pulley. Isolated Ground. 1" Motorola-Style Mounting; Typical for Westerbeke, Lehman, Hino & Pathfinder Engines. 2" Delco-Style Mounting; Typical for Volvo Penta (Gas & Diesel), John Deere, Perkins, Mercruiser, Pleasurecraft, Crusader, Indmar, Marine Power & other GM-based Engines. This product may not be returned to the original point of purchase. Please contact the manufacturer directly with any issues or concerns.