0630 Home Security Door/windows Magnetic Sensor Alarm Entry Alert Chime with Wireless Receiver White Transmitter:68x4816mm,receiver:69x104x23mm Wireless Receiver very sensitive,alert when the magnet set(contact)apart 10mm Sound up to 105dbs,48 pcs different tones in for select; operating range(open area):200M Hight/middle/ low/mute volume adjustable, volume adjustable;Factory 2 year quality warranty. Easy to install with self-adhesive & screws pack. please make sure the surface is clean and smooth for using self-adhesive otherwise please you can use the screws to install the contact firmlyAC receiver with 2 flat plugs,no need to install.