****FACTORY INSTALLED********NOT FOR REFRIGERATED UNITS****Bellco optional temperature alarm module is designed for use with standard 7728 series roll-in incubators including the mini roll-inc.(not refri units). In operation, the alarm module monitors the alarm output of the temperature controller. The alarm value may be set to temperatures between 0-50°c. If the internal temperature of the incubator exceeds the alarm value, then an audible warning is produced. In addition, an internal relay is closed, activating any alarm circuitry connected to the remote jack.. MADE IN THE USA