The Kidde P4010ACLEDS-2 is an integrated 120V AC wire-in smoke alarm with 10-year sealed battery backup and LED strobe light that provides temporal patterns, visual and voice warnings. The model P4010ACLEDS-2 is equipped with a 177 candela strobe light, designed to notify the deaf and hard of hearing. The unique design measures only 2.3” in height, when mounted. If smoke is detected, the P4010ACLEDS-2 will produce a steady flash warning (once per second) and sound 3 long beeps, followed by “Fire!”, repeating. The LED ring will flash red in conjunction with the audible beeps. When triggered by an interconnected carbon monoxide alarm (this unit does NOT detect CO) it will produce an intermittent flash warning (4 times every 5 seconds) and sound 4 quick beeps in time with red LED flashes, followed by “Warning! Carbon Monoxide! ,” repeating every 5 seconds. In an alarm condition, strobe flashes will synchronize with other interconnected P4010ACLEDS-2 and/or P4010ACLEDSCO-2 alarms.