features high strength, to high temperature and abrasion, for long time use. Ultralight, lighter than other material skewers, adding no burden to bike, good for reducing the weight of bike. Tool-free installation, just insert the adapter into the thru axle hub. It converts 15mm thru-axle hub to standard 12mm Nice accessory for your bike. 15 to 12 Specification: Outer Diameter: . 15mm / 0.59inch Inner Diameter: . 12mm / 0.47inch Total Length: . 100mm / 3.94inch Material:metal colour:black Package Contents: 1 * Bike Quick Release Thru Axle Hub Adapter Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.