Check the listing for details. Krown KA300SD Visual Emergency Alert Package. Condition: New. Listed at 229.00 USD. Place the KA300TX Alarm Transmitter next to any smoke or carbon monoxide alarm in your home. Once the alarm sounds, the KA300TX will send a signal to the KA300RX Alarm Monitor Receiver which will alert you by strobe and loud alarm. This kit includes one KA300TX transmitter, which will monitor one alarm. Purchase up to two more transmitters for additional coverage (see KM-KA300TX) KA300RX Features:95dB alarm177mCd strobe light3 alarm channel LED colors: yellow, green and redTime-Condition signal process to prevent "nuisance" alarms1 024 transmitter code combinationsUp to 100 ft monitoring rangeAC adapter (included)Battery backup for audible alarm only (includes 9V battery)Each KA300RX receiver monitors up to 3 KA300TX transmittersPurchase multiple KA300RX units for use in dorms or hotelsFCC, CSA approvedUL listed KA300TX Features:Attach to a smoke or carbon monoxide alarm using included hook and loop fastenerUses CR2032 battery (included)Add up to three KA300TX per KA300RX (available for purchase separately-KM-KA300TX)