Protect The Chain Bicycle Chain Guard Cover High Strength Bike Chain Cover Shell Hardness Chain Guard Lightweight Nylon Description: Specification Name: Folding bike chain ring anti-dropping chain device Material: Nylon Net weight: 12. 6g Gross weight: 30g Applicable: 39-42mm middle tube installation Note: The chainring is not suitable for variable speed, it is only suitable for single-speed chainring. Include: 1*chain guard Specifications: The bicycle chain guide rail can guide the chain and protect the chain from jumping and falling. It is made of nylon pp, with high strength and hardness, and can be used for a long time. Used for single sprocket to make riding smoother and enhance your riding experience. The installation is simple and quick, and it can be adjusted with a wrench without disassembling the crank. It is suitable for mountain bikes with single-chain speed change. It is small in size, light in weight, and has a smooth surface without hiccups. Package Included: 1*chain guard