The digital track gauge is mainly used for measuring the track gauge,check rail gauge,back to back distance,cant super elevation . The instrument is fast and easy to use, and can be used during the day and dark night. digital measurements with the highest levels of accuracy and certainty. Features: 1 Large LED backlit display: especially suitable for daytime and nighttime,tunnel 2 Quick calibration operation: simple measurement process 3 Large capacity battery:long standby time 4 Accurate measurement:keep long-term stability 5 Temperature compensation :working temperature is -30~+55 6 Insulated design 7 Anti-electromagnetic interference 8 Waterproof:could use in rainy day 9 power saving function: no operation within 15 minutes, the system will automatically shut down.