Test Weights of 20kg down to and including 100g are made of high quality grey cast iron. Specification followed is OIML R-52. Shape is truncated hexagonal pyramid. Weights from 20kg to 5kg has one rectangular loading hole on the under surface and 2kg down to and including 100g have one round loading hole tapering outside in the centre of the underside. The weights are finished smooth and free from pits, blow holes and other defects. Weights are protected by a corrosion resistant paint of black colour. The error in excess permissible for adjusted new weights shall not exceed its limits.