Size - Nail Head Length: 6.75mm / 0.27"; Nail Head Diameter: 7.5mm / 0.3"; Thread Size: 5.3mm / 0.21"; Total Length: 13mm / 0.51"; Thread Pitch: 32G Material - Made of hard steel, it prevents rust and corroding, has high hardness, is strong and very wear-resistant, is not easy to break, and has a long service life. Helps improve your running speed and bounce while saving energy, and can achieve better results in competition. Feature - Upgrade tapered needle shape track spikes can increase the friction between the shoe and the ground, prevent skidding and ensure safety. It also improves the balance of traction, flexibility and speed as you run. And will not damage the runway. Application - Provides optimal grip and stability for dry terrain such as athletic fields. General size for most running shoes to use, Suitable for middle and long-distance running, triple jump. If you enjoy running or cross country, these track spikes will help you. Package Content - 5pcs x track spikes.If you have any questions, please feel free to contact us.