Measure up to 2 inches gauge variation while walking down the track. 
Spring-action telescopic assembly expands and contracts as gauge changes. 
Worker can read gauge while walking by looking down at a lens and gauge scale. 
Steel roller bearings measure gauge at 5/8" below top of rail. 
Passes over rail joints but cannot roll through rail crossings or switches. 
Clearance above rail: 1/8". Weight 33 lbs.
 
Shown with optional distance counter and digital level (ordered separately)