... the program in addition to video, intercom, unlock, infrared night visionfunction! 1. outdoor temperature feature: before going ... press, visible,press again, automatically unlockThis system can be used in apartments,villas,hotels,offices ... can use the indoor monitor where the wireless signal can reach,indoor montior can hang ... .4 inch 2.4G Wireless video doorphone doorbell Intercom System 1 V more more V ...