qualty model Fits for Product Details INCLUDES: (1) Selfeed Bit FEATURES: Faster, more accurate drilling: Center feed screw pilots the bit and allows the bit to pull through fast Clean holes: Inside cutting plane shaves the hole radius for clean, smooth holes without pressure Long-lasting performance: Bits are resharpenable and include two removable, replaceable feed screws SPECIFICATIONS: Shank: 7/16" Hex Packaging: Clamshell Hole Diameter: 1-1/4"