[Easy to Use ]We have made transmitter and receiver working and test it it,when you it 't need to do anything ,just install it. STRONG SIGNAL--Adopts RF technology , signal can pass through walls, floors and doors, steadily control receiver from any place within a distance. Max range is up to 984ft with no obstacle. Load: With 30A relay of receiver , which can load high-power electrical appliances to long-term stability control.[Security Control]:Learning code has high-level security for low repetitive rate and re-learn mode, it can delete the code and re-learn a new code,when a remote control lost. So you could always control of it.[Easy to Use]:Extremely easy to setup, learn, relearn and control. Stable and performance, high receive sensitivity.Configuration of two remote controls(alkaline 12V 23A batteries),more flexible use.Wide Application:It is mainly used in ,electric doors,windows,gate,industrial control and security industry and other fields.color:WhiteMaterial:ABSsize:8.53 x 4.37 x 3.02 cmPackage Contents:1 x Receiver module (KR2201B) ( include Shell )2 x Remote Controls (include battery)Only the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.