The unique single-hook design allows easy operation in confined spaces with quick measurement locking. High-strength carbonsteel ensures stability, perfect for pipeline inspection and mold calibration. Three length options, anti-slip surface, includes a portable case. Dedicated single hook for confined spaces: penetrates deep into areas that are inaccessible to conventional tools, such as pipes and gear clearances.Measuring range: 0-300mm, resolution: 0.02 mm High-strength carbonsteel material, anti-pressure and anti-deformation: made of high-quality high-carbon steel, strengthened by heat treatment process, anti-wear, corrosion resistance, even in harsh industrial environments can maintain stable performance, service life far exceeds the ordinary stainless steel material. Easy to operate: Vernier calipers are more durable than dial calipers because they have no internal moving parts, Suitable for lifelong use. Versatile Applications for Multiple Measuring Needs: Designed for versatile applications like machining, automotive repair, woodworking, and 3D printing, capable of measuring hole depth, step height, grooves, and more, making it a must-have for engineers and DIY enthusiasts. Self-contained storage box: each depth gauge is equipped with a protective box, drop-proof and shock-resistant, easy to put into the toolbox or backpack, outdoor work, business trips to carry more convenient, say goodbye to the worry of losing or damaging the tool.