The Yamaha Big Bear Kodiak 400 Wossner Forged Piston Kit +0.50mm 83.43mm 8903D050 is a high-quality piston kit designed for 4-stroke engines. Manufactured by Wossner, this kit includes a piston with a diameter of 83.43mm, providing a reliable and durable option for ATV enthusiasts looking to upgrade their engine performance. The +0.50mm size ensures a perfect fit and improved power output, making it a great choice for those seeking to enhance the efficiency of their Yamaha Big Bear Kodiak 400.