Description:Drillpro 5pcs Hss Cobalt Step Drill Bit Set Multiple Hole 50 Sizes with CaseSpecification: #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") Package Size: 15cm*10.5cm*4.2cm(L*W*H) Weight: 450g Features: This set replaces 50 individual drill bits. Two-flute design gives you faster, smoother cutting. 3-sided (TRI-FLAT) shank will not slip in your drill's chuck. Cobalt coated for smoother cooler cutting. SELF STARTING - No need for a pilot hole. Cobalt coated to reduce friction and run cooler Large bit has 3-sided shank and small bits have hex shank to prevent slip in drill chuck. Automatically deburrs holes as you drill. Long life true M2 high speed steel. Includes protective padded aluminum case. 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