HSS Tool Bits 1. Shape: round, square, rectangle; 2. Allover Length: 4", 6", 8", 12"; 3. ... Material: M42, M35, M2, W9, F4,W4 HSS tool bits:1 ... has different shapes: round tool bits, square tool bits, rectangle tool bits;2. Application: Universal square tool bits are suitable both for cutting metal ... : Overall length:4",6", 8", 12"; HSS tool bits