Material: Our digital calipers are made of high quality plastic, which is not easily damaged and is highly crafted and durable. Multi-purpose: Suitable for measuring outside diameter, inside diameter, depth, whether it is a home project, DIY, or 3D printing, with this caliper will get twice the result with half the effort. Design: Digital caliper intelligent automatic closing function, automatically open when sliding, not in use within 5 minutes automatically closed, effectively save battery power. Date First Available April 10, 2022