As a collector of S&W 22 revolvers, I ordered both variations of the Model 651 when they first came out from a local S&W stocking dealer. The first Model 651 I got was a 4" square butt which is in the "R" serial number range (first of 902 made) and I got it with the extra 22 long rifle cylinder. When they announced that they would be available in a 2" round but variation, I ordered that one too along with the extra 22 long rifle cylinder. There were less than 1300 total 2" guns made so I feel very lucky I ordered one when I did. I believe also that S&W does not offer 22 long rifle companion cylinders any more for 22 magnum revolvers. I have dressed both guns up with smooth Rosewood grips, and was lucky enough to have an aftermarket presentation case for the 2" gun.