Century Drill And Tool 13 Piece Pro Grade Black Oxide Drill Bit Set Lifetime 1-1/8 inch top rim is

1-1/8 inch top rim is permanently rolled for strong reinforcement

Twist drill bit with industrial quality

9” Pad PainterHeavy DutyLocking Swivel HandleCushion Grip

It has a ACME nut x 1/4" inverted male flare

Shot-peened

Century Drill And Tool 13 Piece Pro Grade Black Oxide Drill Bit Set Lifetime 1-1/8 inch top rim isSet includes 1 16 to 1 4 by 64ths drill bits Manufactured from industrial high speed steel, surface treated for high performance and long life M2 grade steel for drilling common steel (flat bar, angle iron, tubing), wood and plastic No center punch needed: Century 135 degree quick cut points are self centering and penetrate faster with less pressurewill not walk or wander at the starting surface Manufactured to Aerospace NAS 907 B specifications. Made