Kidde KN-SMFM-i Silhouette Hardwire Low Profile Smoke Alarm for $13.37. Shipping is free on orders over $25. If needed, use this Filler Tool to pad the order to qualify for free shipping. Here is a screenshot for your reference. It contains a rechargeable battery that runs off central electricity, Ionization sensing technology, and meets UL, NFPA, FHA, HUD, and CSFM standards.
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