VersaDrive Reamers perform the fastest and with less kickback when adapted for use with an Impact wrench for enlarging holes in steel plate up to around 20mm thick. However, they can also be used in any standard 1/2" cordless or pistol drill chuck or adapted for use in a slow speed Magnet Drill. Ideal for use on plate heavier than 20mm thick. Precision 6-flute design for smooth cut on structural steel. Unique design fits in all drill chucks & quickly adapts for impact wrench or magnet drill use! (VersaDrive Adapters NOT included).