11.Brightness and talk volume are adjustable 12.BL-5J battery of camera and monitor is replaceable and rechargeable; 13.Outdoor camera has two work modes: 1) Plugging in the power adaptor. 2) Using battery, it can works about 15 days. 14.With Wireless unlock control ,Tamper alarm function; 15.One outdoor camera supports up to 3pcs indoor monitors and vice versa; 16.The outdoor unit with the function of tamper alarm, and if you keep pressing outdoor calling key more than 5 seconds, will turn off battery battery’s power, once again turn on power.