Features1Outstanding Durability: Made from high strength steel material, this freewheel boasts high hardness, toughness, wear proof performance, and rust resistance. 2Versatile Gear Options: Featuring an 18 21 24T three speed design, this freewheel caters to various riding needs, providing a faster and smoother cycling experience. 3Precise Compatibility: With English thread B1 3.75x24T, this 3 speed freewheel is specifically designed for spin hubs, making it an cycling accessory. 4Smoother Cycling: The cycle freewheel rotates gently, ensuring powerful and smoother operating, enhanced by lubrication for an effortless ride. 5Enhanced Integration: Meticulously machined on precise equipment, this freewheel offers clear threading, secure integration with the hub, creating a tighter and more seamless fit.SpecificationItem Type: 3 Speed FreewheelMaterial: SteelGear Ratio: 18 21 24TSize: Approx. 98x98x16mm/3.86x3.86x0.63inApplication: for Spin Hub, English Thread B1 3.75x24TPackage List1 x3 Speed Freewheel