Limited time promotional. Purchase the Kidde combination gas and carbon monoxide alarm and get a bonus dc basic ionization smoke alarm. Both alarms provide you and your family a level of protection that you expect in a Kidde product. The combination carbon monoxide and gas alarm is easily installed in any of your AC wall outlets, giving you the choice of a direct-plug, a 6ft. power cord or a table top unit. Depending on how or where you wish to mount your unit, you can get exactly what you need for a perfect application. Bonus dc smoke alarm is easily installed, no wiring needed.