Bernstein interchangeable screwdriver sets with esd handle bernstein 4 920 this handy set of double ended interchangeable screwdrivers from bernstein is equipped with an esd handle with a brass clamping sleeve suitable for 4mm hexagon blades this set includes 8 mixed blades supplied in a practical tool roll which is made from conductive material bernstein 4 920 interchangeable screwdriver set with esd handle 9 piece