Universal Security Instruments 6-Pack Battery-Operated 9-Volt Smoke Detector

Dual chamber ionization smoke and fire alarm. Loud 85 decibel alarm. 9-Volt battery operated (included). Audible low battery indicator. Round, flat mounting plate and compact size 4-1/4-in diameter. Fast and easy installation, no wiring required and hardware included. Alarm and power test button. Limited three year warranty. Manufacturer part number SS-770-LR-6P/U.