Well, contrary to popular belief, the chains only convey ears. Tips of the lugs should just protrude past the edge. The snapping roll blades will grab the stalks and pull down them down in the degree directly perportional to the leading edge agressivness or sharpness. Snapping roll blades can be reversed from lH to RH side. Snapping roll blades can also be sharpened with a side grinder if they are not too far gone. One tends to forget how well the new head left the field looking vs the lent over and bent look after a few years. After inspecting many heads I see wear patterns on blades differ from farm to farm depending on how fast they travel and how fast the corn head is run. Also the little rods on the plates are not just wear strips, they are grain ledges. They are a Gleaner invention. Any stray grains bouncing from butt shelling do not fall to the ground off a flat plate as others, but rather are swept into the conveyor by the lugs on the gathering chains. Pretty neat huhIJ