I was in my local shop today looking at the new Martin bows. I picked one up off the rack, don't really remember which one it was, but saw something interesting. I pulled back the rubber off the shelf and saw 2 screws going into the riser. Upon further inspection there appeared to be a seam just above the sight window. Are these risers made in pieces or are they one solid piece of machined aluminum? If they are pieced together, will this have any effect on the strength of the riser?