... cards capacity 6.power supply:DC6V,use of 4 pieces of AA batteries 7.lifetime of battery:door open times, it normally ... them for free. intelligent lock system A. System ConstructionONLENSE set of locks, computer, management software, Encoder, RF card, energy saving switch ... B. working theoryinstall software to computer, card encoder can issue different kinds of card,eg. guest card,master card, ...