Alternator, XT Series, 170A, 12V, Spindle Mount (Single Foot), 1-2in, K6 Serpentine Pulley, Case Ground. 1" Mounting; Typical for Westerbeke, Lehman, Hino & Pathfinder Engines. 2" 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.