A simple multi gauge tool to assist in spotting problems with layout operation. This tool is simple and easy to use with a clear indication of the problem and its location. Simply place the Tester on the two rails of your track. One of three LEDs will illuminate indicating the Voltage on your track. Move the tester up and down the track until you spot the drop in voltage - you've now identified the problem area. Resolve fish plate joint issues and add additional power feeds as required to get your trains moving again! • Suitable for modellers in Gauges Z , N, TT, HO and OO. Plus the matching narrow gauge scales. • Works with DC and DCC controllers. • British designed and made.