Starrett 446AZ-3RL Digital Depth Gauge, Ratchet Stop, Lock Nut, Micrometre Type, 0-3" Range, 0.001" Graduation, +/-0.0001" Accuracy

The Starrett 446 Digital Depth Gauges, Ratchet Stop, Lock Nut, Micrometre Type, Inch, depending on the model, have a measurement range of 0 to 3" or 0 to 6", a resolution (or smallest graduation interval) of 0.001", with + or – 0.0001" of accuracy. The mechanical digital gauge face has white numbers on a black background for easily readable measurements. These units include either three or six, 5/32" diameter measuring rods, to cover the intended range. The bases of these gauges are 3" long, and all measuring surfaces are hardened, ground, and lapped for durability and accuracy. These gauges have a ring-type knurled lock nut to stabilize the gauge for accurate measurements. The metal surfaces have a satin chrome finish that resists rust and improves readability, and a glare-free black finish on the frame. Depth gauges are typically used in manufacturing, machining, and mechanical engineering. Depth gauges are precision measuring instruments used to determine the depth of any shape that has a step, groove, or slot. These gauges often take the form of sliders that travel on a measuring beam or rods, are moved to position by hand, and then adjusted with a calibrated screw. The base of the gauge rests at the top of the shape whose recession is to be measured, while the beam or rods extend to the bottom of the recession to determine the measurement. Gauge position is read from a graduated scale, dial, counters, or an electronic display. The L.S. Starrett Company manufactures precision measuring tools, metrology and testing equipment, and saw blade products. The company, founded in 1880, is headquartered in Athol, MA.