Had a few of these. Might have two left. From what I remember, all weather versions came in .20 carbine. This one has been hanging around in the safe forever. Last time I shot it was around 2005? I remember it grouped well with .20 Ram Jets, as that is an odd pellet that worked well (about 8.5gr.). I remember the stock was farmed out to H&S Precision. It's a pound heavier than other R-1's due to the stock. This one has a trigger shoe that is boxier than the early ones that were curved. Then there is a rear replacement plate. One of the rarest Beeman accessories. A CM sleeve is on the end. Not my first choice, but it is there.