Product : Engine Piston Keychain Size : 7.0*1.5cm Weight : 21g Color :  Gold, silver, black nickel, rainbow plating   This keychain features engine piston designs in metallic finishes (silver, gold, black nickel, rainbow), showcasing a mechanical, automotive-inspired style. Its detailed, industrial aesthetic appeals to car enthusiasts, merging technical symbolism with stylish, collectible accessory design.