Armstrong 66-639 4 Piece Phillips Screwdriver Set Precision Machined, Blasted Tips Provide Superior Fit Between the Tip and the Fastener Reducing Slippage and Fastener Wear Full Shaft Heat Treat Provides Superior Strength That Resists Tip Wear and Shank Twisting / Breakage Fully Polished Chrome Plated Blade Provides A High Luster That Prevents Corrosion Tri-Lobe Handle Conforms to the Hand for Optimal Power and Comfort Solid Impact Resistant Acetate Handle for Uncompromising Durability