The Honeywell Home DC311NBS Wireless Plug-In Doorbell with Pushbutton is designed to address the security concerns that homeowners face. Every home should be a haven of peace and security for its residents. A reliable intruder alarm system provides homeowners with peace of mind, whether they are at home or away. The DC311NBS is pre-linked and ready to use out of the box, featuring a reliable wireless connection and great sound quality. This doorbell includes a wireless plug-in doorbell, a wireless push button, a CR2032 (3V) battery, a quick start guide, a safety and guarantee, and a declaration of conformity. Dimensions: 110 x 70 x 42.5mm (L x W x D).