The T2120 GSR Sensor kit measures minute changes in skin pore size and sweat gland activity (Galvanic Skin Response) or peripheral temperature as they relate to tension. The GSR/Temp 2X™ home biofeedback system allows you to do “hand warming” biofeedback. In addition to the monitor, the system includes a temperature sensor, remote electrodes that attach to the hands or feet, dual-sensitivity meter, earphone, and instruction manual.