These HUSKE Plugs snap into the HUSKE Fork Mount for transporting a bike with a front hub (obviously). Molded from super-durable glass-filled nylon. Sold in pairs. 12x100mm hubs can be found on newer road, gravel, and cyclocross bikes. 15x100mm hubs can be found on many older mountain and cyclocross bikes and newer road, gravel, and cross bikes with disc brakes. 15x110mm/Boost hubs can be found on most newer mountain bikes. 20x100mm hubs can be found on many freestyle and BMX bikes. 20x110mm hubs can be found on many downhill mountain bikes. Specifications for SeaSucker HUSKE Fork Mount Plugs: Manufacturer: SeaSucker Fabric/Material: Glass-Filled Nylon Height: 6 in Quantity: 2 Weight: 1 lb Mount Type: Fork Mount Features of SeaSucker HUSKE Fork Mount Plugs Molded from super-durable glass-filled nylon Designed for 12x100mm Thru-Axle Bikes Package Contents: SeaSucker HUSKE Fork Mount Plugs