1、Long Working Distance: The wireless doorbell has long distance transmission, highly stable signal, and sensitivity, with a maximum opening distance of up to 100m. This doorbell ensures that you hear and answer the doorbell in a timely manner. When someone calls from outside, you will always be easily notified and never have to worry about missing visitors. 2、Simple Installation and Expansion: Use the included screws to secure this outdoor doorbell to your door or wall for more safety. Wireless intercom doorbells are expandable, so you can expand almost any indoor or outdoor system, even to a set of 2 transmitters and receivers. 3、Easy to Install: Just fix the wireless doorbell directly to the wall with tape. Pairing outdoor bell with indoor bell by learning its code, one outdoor bell can pair with multiple indoor bells without interfering with other devices in your home or neighbors. 4、Low Power Consumption and Safe Use: The 2 way intercom doorbell has up to six months of outdoor bell standby time. 5、Wide Application: The perfect wireless doorbell kit is suitable for homes, apartments, schools, offices, warehouses, hotels, factories, hospitals, and more. Adjustable speakers provide clear sound, which can be used as a mobile intercom.