B/W 4 inch CRT pin hole camera, much wider vision Visitor calling, video intercom, unlock, monitor. 1.B/W 4 inch CRT2.Metal outdoor station3.pin hole camera, much wider vision.4.Four wire connection5.Visitor calling, video intercom, unlock, monitor.6.With warning function7.weatherproof and vandal proof out door station8.built-in power adapter available9.Three years' quality warranty(all out door ...