... is rough 150-180m,With micro-dealing technology ,auto-remote contro Wireless Video DoorphoneThis product is with wireless monitoring ,outdoor ... is rough 150-180m,With micro-dealing technology ,auto-remote control , fine characteristics and high reliability,The TFT 2.4" ... night-viewing,24 hour monitoring ,calling , speaking and unlocking remote controlling etc,One indoor video phone can control 6 pcs ...