Teryair Valve Seat Cutter. Valve Seat Cutter is ideal for resurfacing of the valve seat surfaces on most types of valves. Cutters have cutting edges on both sides one side being a slant and the other flat. Cutters are made from special High-speed Steel for cutting. We do our best to present accurate, detailed information about every item we sell. If you are happy with our product don’t forget to leave us your feedback.