The new, adjustable GrooveMaster gives you 8 different options for setting the handle length, providing you with unprecedented comfort and ease of use. Simply press with your thumb to extend or retract the handle to instantly find the handle length that YOU desire. Clean, re-groove and restore your irons in half the time it takes with most of the existing groove sharpeners that are either too small or too uncomfortable to use effectively. The premium cutter head is made from high grade precision tool vacuum heat treated carbide tungsten steel and is unmatched by competing models. The head has 6 groove cutters. Fantastic results on both V and U (square) grooves for the highest spin rates possible. Precision ground and engineered to exacting tolerances to ensure that it does not compromise USGA rules regarding groove width and depth. You benefit by getting the maximum durability and re-grooving effectiveness of any groove tool on the market.