Twenty bucks or so... They sure are nice if you have OLD screws to pull. They will take most any bit and the force of the hammer pushes the bit INTO the screw... where using a wrench might tend to pull the bit OUT of the same screw thereby damaging the screw hole.. The thing is great on rusty Philips screws also.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

professional bovine relocation specialist