"J" HSS Threaded Shank Countersink (1/2") 5/8 Threaded Shank Countersinks while the round shank makes

while the round shank makes them compatible with various tool-holding systems

All 4-flute countersinks have a 1/2-inch shank

1590" BODY DIAMETER 1/2" MATERIAL HIGH SPEED STEEL THREAD SIZE 1/4-28 CUTTING ANGLE 100° SUGGESTED PACK QTY 1

Black oxide surface resists abrasion and improves chip flow

The 135° split point tip ensures fast starts and precise drilling with less walking

"J" HSS Threaded Shank Countersink (1/2") 5/8 Threaded Shank Countersinks while the round shank makesSpecifications PILOT SIZE "J" DECIMAL EQUIVALENT . 2770" BODY DIAMETER 1 2" MATERIAL HIGH SPEED STEEL THREAD SIZE 1 4 28 CUTTING ANGLE 100 SUGGESTED PACK QTY 1 Threaded countersink cutters can be used in adjustable or micro stop countersinking tools with a 1 4 28 threaded drive. They are made from high speed tool steel, precision ground to exact tolerances, and form relieved to ensure a 100 countersink angle concentricity.