You can install the doorbells in locations, such as kitchen, living-room, bedroom, etc. With double side stickers at the back side of the remote button, very easy to install. The special and pleasant of the doorbell has 38 bell songs include for all people to choose;in addition, we also had designed a intelligent flash light at the receiver for the people who was hard-in-hearing. Pretty streamlined appearance shows the elegant tastes of the host. Energy saving design of environment protection. Completely wireless operation - no wires or cables required. Working frequency : 315MHZ ± 2MHZ Door bell powered by 2 pieces AA 1.5V batteries(not included) Remote control / receiver distance : 50m(open area) Color : White & Blue Ring Type : 38 songs Use good quality alkaline battery for doorbells Do not install this product in the sunny or rainy place Please keep some distance between this product and the metal in case it affects the usage The sender and the receiver use the same codes to match with each other Remote controller powered by 1 PCS 23A 12V battery (NOT included) Doorbell chimes provides an extra security and convenience for you and your family, you can put this Doorbell to any places of your room. This Wireless Doorbell is excellent for being used at home, office, shop or any places need to welcome the guests or the customers. The ultra-long distance can reach 50 meters away. it can overcome any obstacles during the course of transmission and receiving, Brand other SKU OT776EL0XYCMONAFAMZ-3075