Durable aluminum alloy hub conversion adapters for front and rear use Material and durability: made from strength aluminum alloy, antirust, resists deformation to maintain hub alignment and performance. Front hub conversion: changes a 100x15 mm front hub to 110x15 mm for expanded compatibility. Rear hub conversion: changes a 142x12 mm rear hub to 148x12 mm to support Booststyle spacing. Essential fittings included: the front and rear hub adapters come with the fittings you need for easy installation and use. Practical benefits: enables wheel and hub upgrades or repairs without replacing the entire wheelset; suitable for riders upgrading to wider or modern hub standards. Compatible scenarios: ideal for bike upgrades, rebuilds, or based wheel where 100x15 front or 142x12 rear hubs need to be converted to 110x15 and 148x12 respectively. Target user: convenient accessory for bicycle enthusiasts and professionals who perform hub conversions. Service and support: we aim to ensure your satisfaction. If you have any questions about the product, we are here to assist.