Overview Reviews Product Description Irwin high speed steel countersinks feature a precision-ground 82-degree tip that makes them ideal for countersinking into most machinable metals.They're made from industrial grade high speed steel for increased durability and they include a black oxide finish for added corrosion resistance.The five flute design reduces vibration for smoother drilling and extended life.Plus, the 1/4" round shank fits all handheld and stationary drills. Irwin Tools Catalog Product Videos Custom Field Manufacturing country CN Product Reviews Write a Review Write a Review × Irwin 3/8" 82° High Speed Steel Countersink Bit 1877715 Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Review Subject * Comments *