This is a brand new, OEM quality, rear differential ring & pinion gear set for the 1995-2005 Yamaha YFM 350FX Wolverine & the 1996-1999 Yamaha YFM 350 Big Bear four-wheelers. This excellent quality part is made to meet or exceed Yamaha OEM standards. It replaces Yamaha OEM part #4GB-Y4612-00-00. This retails for $395.00 from Yamaha