Hydro Pump Drive Belt replaces Hustler OEM#'s 603907, 607400, 607400-A, 607400A, and Ariens/Gravely# 00607400. Specs: 51" x 1/2" Raw Edge Cogged, 0.33" thickness. A&I# B1603907, A-603907, A603907. Similar to Rotary #14939 and Stens #265-699, 265699. Fits all Raptor, Raptor Limited, Raptor SD and Raptor SDX Models. Also fits Big Dog Zero-Turn Alpha and Alpha MP. Refer to your owner's manual to match by belt OEM part #.