Feature: Easy nut slotting and filing. Perfect for filing string slots into nuts. Set of 13 string size 1-13 With the longer shaft length it makes them easier handling for filing string slots. Specification: Material: Stainless steel Each rod length approx:55mm Diameters: .0.4mm-1.6mm as shown in the pictures Weight:12g Note: That these files are especially the smaller ones are thin metal can easily bend and need work slow for smoother slots. Care is recommended when using them so that they will last you a good while. Use is for wood and bone, and soft metals such as brass, copper only. Not recommended for hard or ferrous metals. Package 1 x Set of 13 string saw rods for nut slotting