Profile: Mercury Instruments is a manufacturer of industrial thermometers. Our Mini-AT is a full featured, stand alone, electronic gas volume corrector. Its standard mounting is on rotary, turbine and diaphragm meters that has a rotating shaft output. Our bluetooth wireless technology allows to establish a wireless serial connection with a remote bluetooth device. The dongle is to extract the data from a mercury corrector or other mercury instrument that has the round 9-pin connectors.