Audi a4 anti-theft screws are on the tires, and the tools are under the trunk. Anti-theft screws are also called anti-disassembly screws. The following is the introduction of anti-theft screw: 1. Application: Anti-theft screws are widely used, such as power facilities, railway facilities, expressway facilities, oil field facilities, city street lamp facilities, automobile tires, public fitness equipment, etc. Excellent product performance has been widely concerned and praised by all walks of life. 2. Anti-theft principle: The anti-theft principle of the tire anti-theft screw is to process the shape of the anti-theft screw into an irregular outer diameter shape, and the wheel can only be disassembled by using a special disassembly tool matched with the wheel. So that thieves can't do it with ordinary disassembly tools.