ITEM NAME:Premium Durable Plastic Steel Bicycle Cycling Virtual Flywheel Replacement Set Description: - Premium bicycle virtual flywheel, high strength, lightweight and durable - Used to keep the chain tension when cleaning the chain or during bicycle transportation to avoid scratches - Installation method is similar to the rear wheel - Easy to install and convenient to use - Great spare replacement accessories for MTB, road, mountain, fixed gear bike bicycle Specification: - Material: Plastic, steel - Size: Approx. 39 x 35.2 mm/1.54 x 1.39 inch - Color: Black, silver Package Included: 1 Piece Bicycle Virtual Flywheel Note: Other accessories are not included in the package. Please allow slightly difference due to manual measurement. Color may be slightly different since different monitor. Thanks!.Premium bicycle virtual flywheel, high strength, lightweight and durable. 1 Piece Bicycle Virtual Flywheel. - Used to keep the chain tension when cleaning the chain or during bicycle transportation to avoid scratches.