Battery operated - 9v. Low battery and fault warnings. CO alarm memory. Audible and visual alarms. Test/retest button. Wall-mounted. Digital display.Size: H14.5 x W11.5 x D4.5cm
CommentsGood points: Alarm triggered within three minutes and noise level was over 85db during testing. Level of CO displayed once levels over 30ppm are detected. When test button is held the display shows the previous peak reading. Thorough instructions. Drawbacks: Wall-mounted only. Not obvious what the warnings flashed on the display mean.