Sanding disc 145 mm x 22.3 mm x 4.5 mm for chain sharpener. Suitable for the following devices: Maxx ProGrinder, Jolly, Super Jolly, Jolly Star, Oregon, Efco, Solo Jolly, Speed Sharp, Güde (e.g. Güde P2300, Güder P 2500, etc.), Einhell and other chain sharpeners, the discs in these . 4.5 mm disc for 3/8 inch and .404 inch chains. The discs have the dimensions 145 mm outside and 22.3 mm inside. Depending on the supplier, the dimensions may vary by tenths of a millimetre. With the 4.5 mm disc you can sharpen half and full chisel chains.