New and high quality. This set replaces 50 individual drill bits. Two-flute design gives you faster, smoother cutting. 3-sided (-FLAT) will not in your drill's chuck. Cobalt coated for smoother cooler cutting. Titanium coated to reduce friction and run cooler. bit has 3-sided and small bits have hex to prevent in drill chuck. Automatically deburrs holes as you drill. high speed steel. Includes protective padded aluminum case. Sizes: 1: 3/16" to 1/2" 6 Steps (3/16', 1/4', 5/16", 3/8', 7/16', 1/2') 2: 1/8" to 1/2" 13 Steps (1/8", 5/32", 3/16', 7/32", 1/4', 9/32", 5/16", 11/32", 3/8', 13/32", 7/16', 15/32" , 1/2') 3: 1/4" to 3/4' 9 Steps (1/4', 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4") 4: 1/4" to 1-3/8"' 10 Steps (1/4', 3/8", 1/2", 5/8", 3/4", 7/8", 1", 1-1/8", 1-1/4", 1-3/8") 5: 3/16" to 7/8" 12 Steps (1/4', 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8") Drill1/4-1-3/8 Diameter9mm Drill3/16-7/8 Diameter9mm Drill1/4-3/4 Diameter9mm Drill1/8-1/2 Diameter6mm Drill3/16-1/2 Diameter6mm Material: fast working steel Package included: 1 x 1/4-1-3/8 Step Drill 1 x 3/16-7/8 Step Drill 1 x 1/4-3/4 Step Drill 1 x 1/8-1/2 Step Drill 1 x 3/16-1/2 Step Drill 1 x Aluminum Box Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed is +/- 1-3cm.