1、Made of high quality aluminum alloy, tough and durable. 2、IP-66 waterproof, corrosion resistant, allows outdoor application. 3、Widely used for doors, backpacks, bikes, storage lockers, etc. 4、No need to use keys to unlock, helps you get rid of worrying about keys losing. 5、Easy to unlock quickly with APP in your phone. Universal for both Android and iOS system. Description: This is a smart lock. Made of high quality aluminum alloy, tough and durable. IP-66 waterproof, corrosion resistant, allows outdoor application. No need to use keys to unlock, helps you get rid of worrying about keys losing. Easy to unlock quickly with APP in your phone. Universal for both Android and iOS system. Widely used for doors, backpacks, bikes, storage lockers, etc. Features: Made of high quality aluminum alloy, tough and durable. IP-66 waterproof, corrosion resistant, allows outdoor application. Widely used for doors, backpacks, bikes, storage lockers, etc. No need to use keys to unlock, helps you get rid of worrying about keys losing. Easy to unlock quickly with APP in your phone. Universal for both Android and iOS system. 3 unlocking methods: button / fingerprint / password. One lock can be authorized to many users and a user can unlock multiple locks. Specification: Condition: Brand new Material: Aluminum alloy Color: Golden Size: 9.5 x 6 x 2.3cm / 3.74 x 2.36 x 0.91 inch (Approx.)   Package Included: 1 x Smart lock 1 x User manual(English ) Notice: Please allow 1-3cm error due to manual measurement and make sure you do not mind before ordering. Please understand that colors may exist chromatic aberration as the different placement of pictures.