The Kidde Nighthawk Premium Plus KN-COPP-3 is a premium battery powered (three AAs) electrochemical carbon monoxide (CO) detector with an 85-decibel alarm. The premium features of this detector include continuous digital readout of CO levels and a peak level memory that recalls the highest detected CO level. The peak CO level indicator is useful because it aids in identifying the CO source. Without this feature it is difficult to distinguish between alarms caused by a long exposure to relatively low levels of CO and alarms caused by a sudden high level of CO, which trigger the same alarm. This detector also has a test/reset button for testing and temporarily silencing the alarm, a flip-open cover for easy view of instructions, a power indicator LED, and a 5-year limited warranty. This alarm is recommended for use in hallways and living areas. A manual, three AA batteries, and mounting hardware are all included with the unit.