This package comes with a set of 10pcs skating wheel screws for inline skate replacement. Made of high quality iron with coating on the connecting part, it is durable, sturdy and not easy to loosen. It's easy to install and can be used for a long time. Features: A set of 10pcs female and male skating screws for inline skating wheels. 31mm skating screw is the perfect replacement for the front wheel. 36mm skating screw is the perfect replacement for the rear wheel and brake bolt. Made of high quality iron with coating on the connecting part, it is durable, sturdy and not easy to loosen. Easy to install. Only suitable for skating shoes required the male and female screw fittings on the wheel. Needed two 4mm hex key on double ends for installing. One hex key for fixation and another tool for doing the work. Specifications: Condition: 100% Brand New Material: Iron Color: As Picture Shown Middle Part Length: 31mm, 36mm(optional) Middle Part OD: Approx. 6mm Top Hex Socket Diameter: 4mm Package Weight: Approx. 91g Package Included: 10 * Skating Wheel Screws Note: 1. A difference of 1 mm in length will not influence using. 2. Suitable for male and female nail skates not suitable for single head nail skates.