Designed for use with impact drivers the SHOCKWAVE™ IMPACT DUTY accessory line is not only ideal for heavy duty impact applications, but also delivers a full system solution for all the user's drilling and fastening needs.Laser cut vibration slots filled with polyurethane reduce vibration and increase the accuracy of each blade by acting as shock absorbers and isolating the teeth from vibration.This pack includes 38 assorted screwdriver bits supplied in a storage case.