 | | Tamper resistant locking pins, single button silence/test, and loud 85dB alarm. 120-volt AC power with 9-volt battery backup (included) to keep alarm functioning during power outage. Open mounting design for easy installation with side load battery compartment for quick replacementv and interconnectable up to 18 units (12 smoke, 6 CO/heat/relay). 10-year limited warranty. | | $7.25 More Information |