Wera Bits are designed for the most demanding applications in trade and industry. They are designed to have the ability to transfer high torque loads, safe to use and extremely durable. The greater elasticity of tough viscous bits prevents premature breakages of the tip of the tool.Features Wera’s tough viscous design, for slotted screws,For 4 mm Halfmoon direct drivesWera Bits for hard materials (e.g. metal sheets or structures) prevent premature breakages of the tip, created by the large amounts of peak torque generate to the screw and bit