Checkline J-100 [J-100-A] Dial Thickness Gauge, 10mm Range, 100mm Jaw Depth, 30mm Feeler (A) For rubber, Felt, Soft Materials, Non Wovens, Etc. Measuring range: 0 - 10 mm, Resolution: 0.01 mm. Checkline J-100 Dial Thickness Gauge with 100mm Jaw Depth. The J-100 (metric) and JZ-100 (imperial) thickness gauges are designed for measuring the thickness of leather, textile, cardboard, felt, rubber, sheet metal, foils, plywood, plastic parts of all kind, etc. The aluminum housing is lightweight and rugged. It can be easily zeroed by turning the outer knurled ring of the scale.