Dwyer Series BTT Temperature Transmitter - Duct MountThe Series BTT Temperature Transmitters offer transmitter output signals with the same form and fits as our popular TE Thermistor and RTD sensors for building HVAC applications. Duct Mount shown here Models for Liquid Immersion and Outside Air shown separately; Output 420 mA or 010 VDC; 2 Wire Loop Powered; Only stocked configurations shown (others on request);