7pcs (1/8"-1/2") Multi-Purpose Drill Bits Set in metal box

1) Product: 7pcs inch size Multi-Purpose Drill Bits 

            1/8"-1/2" by 1/16" increments

            size of 7pcs: 1/8", 3/16", 1/4", 5/16", 3/8", 7/16", 1/2"

2)Picture of multi-purpose drill bits 7pcs/set

3)Drilling instructions

Please follow the speed and technique instructions below

Hardened Steel and Iron            2000—4000 RPM (Lubricant)

Masonry/Concrete                 2000—4000 RPM (Percussion)

Stainless Steel                    1500—2500 RPM (Coolant)

Glass/Tile/Granite                  300—600 RPM

Plastic and Laminates               300—600 RPM

Solid Surface Materials              300—600 RPM

Wood and Composite                500—1000 RPM