Half Round Needle File #4 Cut This versatile Half Round Needle File features one Flat side, and one Half Round side for removing sharp edges and excess metal on Wire ends, Sheet, or Cast jewelry pieces. The #4 Cut is a very fine grit cutting File, which requires almost no polishing after use. Length: 5-1/2" Cutting grade: #4 Why do I need this item. This is a great tool for finishing any remaining rough edges on sheet or wire on your latest Wire Project.