Features 40MN material: bicycle chainrings are made of durable 40MN material with high hardenability, strength, hardness, toughness and durability. [Recyclable] This bicycle chain link can be reused and the disassembly and installation of the chain are very convenient. Extended service life: The chain main link roller prevents thermal cracks in cold weather due to intense heating and cooling during the race. Sufficient quantity: the set contains a total of 20 chains, each of which can be reused. This set will last a long time. [Main use] Chain main link rollers are suitable for mini bicycle trolleys. Specification: Item Type:Chain Main Link Roller Material: 40MN Model: 35 1 cl Package list: 20 x chain guide rollers. 1 x storage box. Small note: Please check the width and model of your bicycle chain before ordering the missing link for these bikes. Package List 20 x Chain Master Link Roller 1 x Storage Box