Check the listing for details. GR-12 Tungsten Sharpener Grinder,Electrode Sharpener Grinder Head Welding Tool. Condition: New. Listed at 37.00 USD. Easy installation: Easy to install,designed by a professional welder, grinding any size tungsten at 10°, 15° and 20° angles. Wide Compatibility:Fit for all rotating tools with 3/4 ‑ 12 thread.