It's convenient for you to change the tacks. There is enough quantity for your daily use. Made of high class rubber material, very strong, rust and corrosion resistant. Well-designed, no damages to the track, just rest assure to have your training on track. It is easy for you to screw the track nails into the shoes, which is convenient to replace the spikes. Features -Color:As Shown-Material:Rubber -Size:2.00X2.00X1.30cm/0.79X0.79X0.51in-These spikes are designed with needle shape for increasing the friction between shoes and ground.-Rubber material, light weight, good elasticity, prevent easily rust and corrode.-Each shoe spike measures the length, which is the general size for most running shoes to use.-If you are fond of the running, or you're a sports enthusiast, you must not miss this!-Not easy to lose when running, These spikes are suitable for all athletic tracks. Packing list: 25 x Shoe Nails