Features: Waterproof design, airtight space, water without holes to enter, outdoor use without worries. 5V charging current, can connect to computers, mobile phone chargers, Mobile power supply and other equipment to charge. Intelligent monitoring, vibration alarm. When the external force vibration is felt, 110 decibels super alarm sound will be issued. Over 5 times more than non-alarm locks, effectively deter thieves. Intelligent sharing. APP unlock key can be shared directly with friends and relatives. A mobile phone can control many locks and manage many bicycles at the same time. Strong anti-riot and anti-riot ability. Lock body is made of heat-treated hard alloy steel, and the lockpin is made of 304 stainless steel, sturdy and durable to use. Intelligent management, automatic unlocking. When the mobile phone approaches, it can automatically unlock, and when the mobile phone leaves, it can automatically unlock. Intelligent positioning, lock when the hole is encountered. Put the lock on the disc brake disc and press the lock key to lock. Applicable to most mobile phone brands in the market. Apply for iOS version 8.0 or higher and for Android version 4.3 or higher. Specifications: Working voltage: 4.2 ~3.3 (Built in 3.7V 350mA polymer rechargeable battery) Standby current: Unlocking mode: