Pack of two smoke alarms is by leading brand Kidde Ionisation sensing technology that may detect invisible fire particles sooner than photoelectric alarms These alarms are battery operated (2 x batteries included) It is easy to fit as there is no complicated wiring, it just simply mounts to the wall Dimensions: 12.5cm (Diameter) | 3.8cm (Depth) (Approximately) This pack of two smoke alarms is by leading brand Kidde. Their compact size make them ideal for installing in a variety of places around the home. They are easy to fit as there is no complicated wiring, they just simply mount to the wall. They both feature hush buttons, test buttons, a loud alarm, flashing light that indicates that the alarm is operating and a low battery warning signal. The only difference is that the i9080EU model has an emergency escape light designed to guide you to safety in the event of smoke or fire in the home. They have ionisation sensing technology that may detect invisible fire particles sooner than photoelectric alarms. These alarms are battery operated and each use 1 x 9V super alkaline battery. A fantastic quality product by Kidde that is reliable. It features a test button and hush button and it includes 2 x 9v batteries are included and necessary screws for mounting it. The dimensions for both of the smoke alarms are approximately: 12.5cm (Diameter) and 3.8cm (Depth). Model Number: i9060EU and i9080EU. It is recommended that the battery is checked before installing. This product is being delivered from the UK by International courier. Your item will be despatched within 1 day of receiving payment. Typical delivery time is within 7 days.