Features: 【High quality material】 Made of hard metal, these kind of tire stud screws are strong and durable in use. 【Performance】  It has a low ground pressure and it is environmentally with minimum impact. 【Function】 This kind of screws are suitable for most of tires. It brings a good anti-slip property for your tires. 【Convenient】  It is easy to install with certain drill and can match well with your vehicle tires. 【Advise】 Please choose appropriate size of new studs in the installation process in terms of the depth of tire thread.  Specifications: Material: Metal Color: Silver Item Size: 1.2 x 0.4cm/0.47'' x 0.16'' Diameter: 0.2cm/0.078'' Item Quantity: 100 pcs/bag Package Weight: approx. 74g 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. Package Included: 100 x Tire Stud Screws Note: It is easy to install, but professional installation is highly recommended.