Permatex Valve Grinding Compound Aids Valve Grinding And Seating Operations To Remove Burrs, Surface Defects, Carbon, Gum And Corrosion. It Can Be Used For Lapping And Grinding Chromium. Mixes With Water To Form An Easy-To-Use Paste. Use For Hand Or Machine Grinding. Mixes W/Water To Form Easy-To-Use Paste. Removes Surface Defects, Burrs, Corrosion, Carbon.