SWR Test Meter. CB Radio Frequency Range 27 MHZ. SWR 1:1 to 1:3. 52 ohm impedance. SO-239 Input and Output Connectors. Heavy Duty Metal Case Dimensions: 3 3/8 X 2 1/4 X 3 in. Includes: 3' Black Workman CX-3-PL-PL Coax Jumper