Dial Snap Gauge Graded Aluminum casting ensures light weight and handy frame. Other steel parts hardened & round.Measuring face is made of Tungsten Carbide for great wear resistance.Parallelism of measuring face is in the range of 0.003mm up to 150mm.Available in 0mm-25mm, 25mm-50mm, 50mm-75mm, 75mm-100mm, 100mm-125mm, 125mm-150mm ranges.Any standard dial indicator with 8mm dia. holding shank can be fitted easily.