This recall involves Sure Signal Products heat-activated fire alarms sold under the following brand names and models: DeTech FST2004H, MasterGuard QR50, Responsive TR70-R and Thermalink QR50. They are white, round and measure about 7 inches in diameter. The alarms have a round fuse at the center. The fuse is white or chrome and about 1.5 inches in diameter, and has a temperature rating of 117°F or 136°F. The alarms were manufactured from January 1, 2004 through July 1, 2015. Date codes are listed in a YYDDD format and range from 04001 through 15182. The alarm’s model is printed on a label on the back of the alarm. SSP, the temperature rating and the date code can be found on the back of the fuse.