Vending Machine Patent Lock Manufacturer in China: Patent Lock for Vending Machine, Zinc Alloy, Multi Internal Security Mechanism, Bright Chrome. Material: Zinc alloy. Finished: Bright chrome. Key combination: 6,000,000,000. Applications: Vending machine, game machine, safety box, ATM, electrical cabinet, street kiosk, locker, automatic book machine, automatic cd machine etc. Specialty 1. Over 6 billion key code and unique key shape. 2. Multi internal security mechanism. 3. Creative design with smart disc & tumbler.