Eze-Lap I carry the little brass tube style in the field and keep the 12" oval diamond at home/truck. Dosen't take much to put a razor edge back on. Just have to keep the same angle, once you get the feel it's not too hard. One trick I do if having problems is I'll color the edge with a sharpie, that way I know where I am removing the metal from and if not feeling the drag on the stone clean it. It will get metal built up on the stone, just wipe it with a damp scotts brite.