The CMD6-M is the most advanced marine CO alarm on the market, featuring a state-of-the-art sensor that is unaffected by common cleaning solvents. The ultra low current draw of the new sensor allows us to offer the only marine battery powered CO alarm on the Market. Experience Fireboy-Xintex quality and reliability on board. Features CMD6 use the same housings, mounting bracket, and wire connections as CMD5 CMD6-MB battery model will be 100 percent powered by the permanent internal batteries and needs no external power CMD6-MD 12-24V DC model uses boat power and has permanent internal backup batteries if the boat power goes out No boat-RV battery draw, no circuit breaker, no wires to run, and much less labor to install Only battery-powered marine CO alarm on the market R version that will include an internal relay and the Interconnect function Specifications Color: White Alarm Point: 10% COHb Alarm Horn: 85 dBA Interconnect Functionality: No Dimension: 0.5" x 3.5" x 1.21" Weight: 1 lbs