The BlueSpot 10 Piece Assorted Diamond File Set is suitable for precision work on intricate materials including carbide, glass and hardened steel. Diamond-coated. Includes handy carrying pouch for quick and convenient storage.. Diamond tips for increased strength and durability. Suitable for precision work on intricate materials including carbide, glass and hardened steel. Includes handy carrying pouch for quick and convenient storage. Length : 145mm (5.7"). .