Mission Chromoly Hub Guards are a great option for riders looking to protect their hubs and spokes from grind damage. Universal design slides over existing hardware for easy installation and works with a wide variety of 3/8" front and 14mm rear (non-drive side) BMX hubs. The guards are made from chromoly for maximum strength and long lasting durability. Mission Front Guard- Fits most 3/8" male and female axle front hubs. (2.1 oz) Thickness: 1.5mm, Overall Width: 12mm, Outer Diameter: 65mm Mission Rear Guard- Fits most 14mm male axle hubs and female axle hubs that use 14mm axle bolts. Works on non-drive side only. (3.7 oz) Thickness: 3mm, Overall Width: 25mm, Outer Diameter: 75mm