Normally, whetstone-polishing whetstones are used by placing the whetstone to be polished on top and rubbing the surface on it. With TAIRAGAIN, on the other hand, you can place the whetstone and rub it back and forth, keeping the surface flat until finished.
A large-type whetstone with dimensions of 400 x 200mm, it can be used for speedy polishing even for bigger whetstones. If the whetstone is diminishing too much, first use the #20 side to polish out the rough surface, and finish with the #120 side or another finishing whetstone.
This whetstone-polishing plate is very useful also for slight surface refinement, with the #20 side for polishing the rough surface and the #120 side for use as a medium and finishing whetstone.