Kincrome Impact Driver Set 5/16" & 1/2" Drive 14 Piece ID3400The Kincrome Impact Screwdriver Set is designed specifically for effective fastening and loosening of rusted, damaged or stripped fasteners in heavy duty applications, such as larger fasteners used on a car or industrial machinery. It does this by applying a strong, sudden rotational force coupled with forward thrust when struck with a hammer to 'shock' fasteners loose and prevent the tip from camming out of the fastener. It utilises 5 16" hex drive