There are one inside caliper and one outside caliper, inside caliper is available in the same size range as outside caliper.<br> Wide application, Can be applied for sculpture, pottery, tube and so on.<br> The caliper is light and small, so you can easily carry this clay sculpture tool to somewhere.<br> Excellent workmanship, smooth surface and edges without any burr.<br> Made of stainless steel for superior hardness that reduce wear- outs and insure longevity.<br> Features:<br> - Steel calipers with hardened and finely polished tips for durability.<br> - Inner caliper measures distance between aperture and surface.<br> - Outer calipers measure the thickness and outside diameter of an object.<br> - Lightweight and easy to handle, the calipers transfer measurements of internal and external dimensions from model to clay.<br> - Ideal for measuring external and internal dimensions that cannot be reached with regular calipers, such as sculpture, pottery, and pipe.<br> - Material: steel.<br> - Size: 30.00X1.50X0.50 cm/11.79X0.59X0.20 in.