Kidde i12020 Hardwired Smoke Alarm with Hush Button, Interconnectable Hush feature temporarily silences nuisance alarms One touch test button tests unit's electronic circuitry Quick connector makes installation fast and easy Tamper resist locking pin helps deter alarm tampering and theft Kidde?s smoke alarms meet the requirements of Underwriters Laboratories (UL), an independent facility that tests products for compliance with widely-accepted safety standards