The Kidde Micro Smoke Alarm with Hush Button (KIDI9040UK) is a compact smoke alarm, which is easy to install. It features a test button to check the battery and alarm is operating, and a hush button to silence false alarms, e.g. when cooking. It is CE marked and tested to: EN 14604. This alarm uses an ionisation sensor to detect fast flaming fires. It requires a 9 volt battery which is supplied. This unit is ideal for use anywhere in the home and provides effective protection when used alongside other smoke alarms.