Millimeters & Inches Brass Deluxe Sliding Pocket Size Gauge Great for Measuring. This is a new brass deluxe sliding pocket size measuring gauge. Great for measuring small stones and small parts. Eliminates the problem of holding while measuring by placing the stone or part on the metal underplate to get a fast, accurate measurement. Has a smooth brushed finish and fine, crisply stamped numbers and lines. Measures millimeters and inches. Graduated in 1 mm and 1/16" increments. It measures up to 80 mm and 3 1/4".