4 - Hardwired Heat Alarm with Battery Backup BRK Brand HD6135FB

The BRK hardwired heat alarm unit alarms if either the temperature reaches 135 degrees Fahrenheit or the temperature rises more than 15 degrees Fahrenheit in one minute. Product Details: Manufacturer: ‎First Alert / BRK Brands Inc. Part Number: ‎HD6135FB Item Weight: ‎8.5 ounces Product Dimensions: ‎11 x 9 x 5 inches Country of Origin: ‎USA Item model number: ‎HD6135FB Is Discontinued By Manufacturer: ‎No Color: ‎Original version Power Source: ‎120-volt AC/DC with 9-volt battery backup Voltage: ‎120 Volts Item Package Quantity: ‎1 Number Of Pieces: ‎1 Cutting Diameter: ‎5.5 Inches Included Components: ‎BRK Brands HD6135FB Hardwire Heat Alarm with Battery Backup Batteries Included?: ‎No Batteries Required?: ‎No Assembled Diameter: ‎5.5 Inches Meets UL requirements.