Dimar 50018 #8 Carbide-Tipped Countersink Drill Bit by Dimar $29.95 SKU DIMAR 50018 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart 1/4- Inch Hex Shank Design for Quick Release For #8 Wood Screw Size Cutting Dia: 1/8", Countersink Dia: 3/8" Premium Carbide Tips - Professional Quality