The Techko S189D Ultra Slim Pool Safety and Entry Alarm is designed to sound a loud alert when a door or gate is opened, The magnetic contact sensors are installed on the gate or door you wish to secure, Once installed, it will allow adults to pass through the protected gate or door by pressing the bypass button, Once the bypass button is pressed, the adult will have 8-12 seconds to pass through and shut the gate, The Entry Alarm is a simple solution for alerting you whenever your children and others enter and leave the pool area, The Ultra Slim Pool Safety and Entry Alarm can alternatively be used as an alert system for other door and gate entry areas in and around your home or property, This product is powered by three AAA batteries, included, The Ultra Slim Pool Safety Alarm with Extra Sensor is ETL listed and approved under UL 2017 standards, This kit includes 2 magnetic contact sensors, ideal for pool areas with multiple gate or door entry points, It is also available with 1 sensor and a remote bypass button, ideal for pool areas with a single gate or door entry points, Magnetic sensor entry alarm, Always on alarm protection, Adult pass-through auto reset button, High output 110-115 dB alarm, Waterweather resistant housing, Magnetic sensor for additional doorscreen door, Low battery LED display, Ultra thin design, Additional pass-through button for delayed entry from either side of door or fence, Additional magnetic sensor for screen door exitentry, Intended for interior or exterior use, 3 1, 5V AAA batteries included, Pool Guard Alarm USA Patent No, 5,473,310, No, 6,727,819, and No, 7,187,280, ETL Approved under UL 2017 Standards!, Dimensions: 4, 75 L x 0, 75 H x 1, 75 H, SKU: TCKO014