The P2+R2 Combination Bit works with Phillips and Robertson (square-drive) screws, which eliminates bit changes and increases productivity. Constructed from high-grade steel, it comes as an insert bit or as a 1 1/2-inch or 2-inch power bit for use with ultra-compact cordless tools. Cost: Under $5 for 15-pack of 1-inch bits. Bosch Power Tools and Accessories. 877-267-2499.