Description: This package comes with a set of 10 skate wheel screws for replacing skates. Made of high quality iron with coating on the connecting part, it is durable, sturdy and not easy to loosen. It is easy to install and can be used for a long time. Features: Set of 10 Female and Male Roller Screws for Roller Wheels. The 31mm skate screw is a perfect replacement for the front wheel. The 36mm skate screw is a perfect replacement for the rear wheel and brake screw. Made of high quality iron with coating on the connecting part, it is durable, sturdy and not easy to loosen. Easy to install. Suitable only for skating shoes, requiring male and female screw connectors on the wheel. For installation, you need two 4 mm hex keys at the double ends. One hex key for fastening and another tool for doing the job. Technical data: Material: Iron Color: as shown in the picture Middle part length: 31mm, 36mm (optional) Middle part OD: approx. 6 mm Upper Hex Socket Diameter: 4mm Package weight: approx. 91g The package includes: 10 * Skating Wheel Screws The length difference of 1 mm will not affect the use.2. Suitable for men's and women's skates, not suitable for single-head skates. . 10pcs replacement roller skates screws 31mm