Vehicle Detector, Includes Relay, Number of Channels 1, Operating Voltage 10 to 30V AC, Minimum Loop Inductance 20 uH, Maximum Loop Inductance 1,500 uH, Features Automatically Compensates for Loop and Lead-in Sizes, LED Indicators, Removable 7 Pin Terminal Block, Resistance Properties Impact , Overall Height 1 1/2 in, Overall Length 1 1/2 in, Overall Width 3 in, Minimum Operating Temperature -35 Degrees F, Maximum Operating Temperature 165 Degrees F