A straight grinder or die grinder is a hand-held power tool with a rotating spindle on which a collet and cutting bit are mounted. The die grinder rotates at very high speed, and is used to remove material from a workpiece or surface. It is perfect for machining small areas for which a regular one-handed angle grinder is too large. Die grinders can be operated by compressed air or electricity.
With a die grinder and the right cutting accessory, you can polish, grind, cut or finish many different materials. This makes the die grinder very versatile in many different circumstances.