VersaDrive ImpactaTaps for Galvanised Bolts have an oversized thread to compensate for the increased thickness of coating found on galvanised steel fabrications or galvanised fixings. VersaDrive ImpactaTaps perform best when adapted for use with an Impact wrench for through holes. However, they can also be adapted for use in a reversible Magnet Drill, or even used with any standard Hand Tap wrench. Fast Tapping with Minimal Kickback; Specially hardened for Impact Wrench use. Chipbreaker action for Automatic chip clearance when Impact Tapping. Unique Dual-Point Starting Angle for easy alignment and fast cut. High Grade Tool Steel with Ground Flutes for high accuracy & long life. High Strength, Non-slip Shank Design. Galv Taps have an oversized thread to compensate for the increased thickness of coating found on galvanized steel fabrications or galvanised fixings.