SimpliSafe Extra Entry Sensors (Pack of 2)

The magnet is going at the door or window, and the sensor is going at the
frame (or vice versa). Magnet can also be placed as much as 2 inches from the
sensor, so sensors fit on all varieties of doors and windows. SimpliSafe
sensors come with the battery pre-installed and adhesive tape
pre-applied, making installation a snap.
Simplisafe Extra Entry Sensors (Pack of two)
Defend Your Windows and Doors
Easy to Install on Each Form of Door or Window. The magnet is going at the door or window, and the sensor is going at the frame (or vice versa). Magnet can also be placed as much as 2 inches from the sensor, so sensors fit on all varieties of doors and windows. SimpliSafe sensors come with the battery pre-installed and adhesive tape pre-applied, making installation a snap.
Door Chime. When your system is OFF and a door or window opens, the Base Station will sound a door-chime so you can know if any individual is entering.