Tread Wear Measuring Gauge as per RDSO Drawing No. SKDL- 3592, Alt. 6 or latest, Shoot to model TWG- 1 of PIE Brand ( or ) equivalent for thick wear adopted profile for BG ( Diesel & A. C. Locomotives ), Made of stainless steel with Hardened steel wheel wear measuring pointers, Gauge has laser etched permanent measuring sacle for easy to read precise reading.