About This WING NUT - Measuring pottery tool adopts wing nut, which is much easier to tighten and loosen connections, and keep them to the desired tension for accuracy. RETAIN THE MEASUREMENTS - Firm joint calipers use friction at the joint to hold the legs not move, can hold the measurements without slipping, great for making consistent size. TOUGH STAINLESS STEEL - The caliper is made of durable stainless steel with hardened and finely polished points, 254mm(10") long, sturdy, high hardness and wear proof. CLAY CALIPER TOOL - The clay sculpture tool is lightweight and easy to handle, ideal for pottery clay sculpture measuring, a practical tool for professional clay sculpture worker or a craft amateur. SERVICE GUARANTEE - Caliper clay pottery tool holds in place easily, great for you to measure the external and internal dimension of an object. Overview Brand : Watris Veiyi Material : Stainless Steel Product Dimensions : 0.55"W Range : 1E+1 Inches Measurement Accuracy : +/-0.001 inches