Lengthening shims fit over the stripper screw threads and under the shoulder which, in effect, lengthens the stripper screw length. Made from a 302 full hard stainless steel. Fits six different shoulder screw sizes from 6 to 20 mm Dia. Precision Brand® 330-piece metric lengthening shim contains 10 each of the following sizes in six thicknesses (0.125 mm, 0.25 mm, 0.4 mm, 0.5 mm, 0.65 mm and 0.8 mm): 5.92 mm ID x 7.95 mm OD, 7.82 mm ID x 9.95 mm OD, 9.7 mm ID x 11.96 mm OD, 11.65 mm ID x 15.94 mm OD and 15.5 mm ID x 19.93 mm OD and 4.95 mm x 5.96 mm in 0.125 mm, 0.25 mm and 0.4 mm. Precision Brand® Lengthening Shim Kit, 302 Full Hard Stainless Steel, 0.25 mm Minimum Thickness, 0.8 mm Maximum Thickness, 4-1/4 in Width, 8-1/4 in Length, 330 Piece