ITEM NAME:15* 3 4 5mm HSS HIGH SPEED STEEL TITANIUM COATED DRILL BIT 1/4'' Pro SET H4P6.HSS drill bit set for wood, plastic and aluminum, copper, steel. Material: HSS. 5pcs x 3.0mm HSS drills. 5pcs x 4.0mm HSS drills. 5pcs x 5.0mm HSS drills. Surface: titanium coated. High speed steel, durable.