Replacement for Mercedes Benz Security Master Locking Wheel Nut Key 306 Anti-theft Screw Socket Wrench Tool NOTE: PLEASE MATCH IMAGE TO YOUR LOCKING NUT. Features: A Wheel locking key is a security device designed to prevent your wheels from being stolen. It wouldn't be such a great security device if all cars had the same locking key. Your car could have one of hundreds of locking keys installed so it is important that you check the pictures match the locking nut on your car before purchasing. Specifications: Color: Silver Material: Steel Package size: 3.7 * 2.8 * 2.8cm Pacakge weight: 105g  Package List: 1 * Anti-theft Screw Socket Wrench Product Use Advice: Please lubricate locking nut before using this tool. Not to be used with impact gun. Tighten to correct torque for vehicle (Usually 110-120Nm - Check Manufacturers Recommendation). Not to be used with "overtightened" locking nuts (Nuts barely feel tight at correct torque).