This 44-piece impact driver screw bit set from BLOSTM is constructed from durable S2 shock-resistant steel for lasting use and enhanced hardiness. Designed for use with impact guns, it allows for quick and easy driving of screws and fasteners into tough materials. The set includes 39 driver bits, a 120mm retracting screw sleeve holder, a 35mm countersink bit, a socket adapter, and nut drivers (6 and 8 mm). All bits are coated with manganese phosphate for enhanced protection, lubrication, and longevity. This professional-grade set is suitable for professionals, DIYers, and homeowners for any type of project.