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First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide Alarm with Battery Backup : Amazon.co.uk: DIY & Tools
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First Alert 9120BA Hardwire Smoke Alarm w/ 9V Battery, Smoke Detector, Combination Smoke & Carbon Monoxide Detectors - Amazon Canada
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First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide Alarm with Battery Backup : Amazon.co.uk: DIY & Tools
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