Electronic lock The key with inner circuit board internally installed, no need memorize the passwords. The key is antimagnetic, waterproof, shockproof without the need of external power. Zero rate of opening locks mutually, anti technology unlocking. The digital key can't be copied slinkingly, no need to have the worry of losing. Users can copy the digital keys discretionarily at their options, simple and safe. The digital key has the user-key, management-key and project-key functions. One digital key can be set to open several doors at the same time Adopt the traditional unlocking way. The circuit contains spare system. Warning alarm when invalid key is used. Warning alarm when forgetting to draw key. Warming alarm when low battery. Low electricity consumption, the common battery can work for more than 1 year. Modularization designing, simple installation and convenient maintenance. Perfect combination of mechanical and electronic door lock, high anti-destructive capacity. Mt circuit, safe and reliable 9 to a carton, the size of the carton is 53.5cm x37cm x29cm and gross weight is 36kgs