The traditional Bevel Eze is used to take off the square edge on a leather strap. It has a cutting edge that removes a slither of leather from a strap edge. The tool can be used to remove the edge from the top side and also the back of leather. After using the bevel Eze it is recommended that the leather edge be polished with an edge slicker. Size 4 takes the 2nd largest amount of leather off and in used for thicker leathers about 3-4 mm.