Features: 1.Applicable Model: The chain slider swing arm guard kit is a replacement for Thumpstar CRF50 XR50 SSR TTR, wide applicable for 50cc?160cc Chinese Pit Dirt Trail Bike Motorcycle. 2.Chain Roller Tensioner: The chain roller pulley tensioner can provide a smoother riding experience, which is useful in effectively reduce wear and prolong the service life of the chain. 3.Chain Roller Protector: Can prevent chain from sliding out and increase safety while motorcycling. Help protect swingarm from abrasion to lengthen its service life. 4.Swingarm Guard Chain Guide: Lightweight one piece design that allows for simple install and protection against breakage of your chain guide tabs on the swingarm. 5.Practical in Use: The chain can have proper tension during the transmission process, so as to avoid its slippage, or avoid jumping, tooth loss and coming out. Specification: Item Type: 10mm Chain Roller Tensioner Kit Material: Metal, ABS Application: Applicable for Chinese Pit Dirt Trail Bike Motorcycle 50cc-160cc Replacement for Thumpstar CRF50 XR50 SSR TTR 50cc-160cc