Feature: 1. These stds screws is made from hard metal alloy, super strong and sturdy in use. 2. Easy to install with certain drill, can match well with vehicle tires. 3. Can be removed lightly and stored for nest use in following season. 4. Low ground pressure and environmental friendly with minimum impact. 5. Fits for most tires and adds off road capacity to car, truck, motorcycles, etc. Specification: Installation: Drill (using a very small bit) down from the center of chosen knob into the tire. Drill a screw up from inside to out. If the angle isn't perpendicular to the tire, it will stick out one side or the other. Do one hole and screw at a time. Put duct tape over the screws on the inside of the tire. Sometimes it is best to use two layers of tape. Specifications: Material: Steel Alloy Color: Silver Quantity: 520Pcs Item Size: Shown as pic. Package Size: 15*10cm / 5.9*3.94in Package Weight: approx. 330g / 11.64oz . Package List: 520 * Tire Stud Screws 1 * Drill Sleeve Note: Please choose appropriate size of new studs in the installation process in terms of the depth of tire thread.