First Alert SM210 Sealed 10 Year Battery Smoke Alarm with Slim Profile Design ESI 3 mm thickness has flawless touch 3P2059 CHELCA120BLK 3 mm thickness has flawless touch response with high sensitivity The Quick Read Message Counter lets you easily check for messages and listen to them from the landline base unit or cordless handsets The First Alert SM210 10 Year Sealed Battery Smoke Alarm with Slim Profile Design is equipped with First Alert's Precision Detection advanced sensing technology and meets new industry standards to reduce cooking nuisance alarms and provide early warning in the event of a home fire emergency Test silence button for efficient testing to ensure the detector is working properly