Mains Powered Optical Smoke Alarm with Back-Up Battery - Kidde Firex KF20

The updated Kidde Firex KF20 and KF20R alarms are mains powered, interlinking optical smoke alarms that use up to 70% less energy than previous Firex models. The KF20 has an alkaline battery back-up and the KF20R, a self-charging lithium battery back-up.

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