It consists of a pair of steel elements, with ergonomic handles, and is intended for single-handed operation, so that you will have the other hand free to handle the workpiece. It has a millimetre-scale with double nonius. On the main graduated scale there are lines every 5 mm, while the secondary scales enable you to measure millimetres and five-tenths of a millimetre. Available in two sizes, small (max. thickness 10 cm, max. depth 17 cm) and large (max. thickness 15 cm, max. depth 31 cm). Max. measurement depends on the shape of your vase and bowl.