For Blind Hole with Setting Rings, Range 6-100mm• Self-centering 3-point for accurate measurement of internal diameters. • Highly durable because of carbide-tipped contact points.• Measurement can be taken closer to the bottom of the blind bore and can be taken into a deep hole with an extension robs. • Supplied with setting rings • Within 12mm/0.5'': Resolution: 0.001mm(Metric); 0.0001''(inch) Over 12mm/0.5''Resolution: 0.005mm(Metric); 0.0002''(inch) RangeGrad.Model No.RangeGrad.Model No.6-8mm0.005mm600-220130-40mm0.005mm600-22198-10mm0.005mm600-220240-50mm0.005mm600-221110-12mm0.005mm600-220350-60mm0.005mm600-221211-14mm0.005mm600-220450-63mm0.005mm600-222112-16mm0.005mm600-221760-70mm0.005mm600-221314-17mm0.005mm600-220562-75mm0.005mm600-222216-20mm0.005mm600-221870-80mm0.005mm600-221417-20mm0.005mm600-220675-88mm0.005mm600-222320-25mm0.005mm600-220780-90mm0.005mm600-221525-30mm0.005mm600-220887-100mm0.005mm600-222430-35mm0.005mm600-220990-100mm0.005mm600-2216