I own an H&R 732 as well as a 929. Both with the square butts. Theyre the same size. Tyler and BK only reference S&W frames as well as Colt. I assume they are equivalent to a K frame but it could be L, J even or Colt D. They've suggested the size J fits an H&R topbreak, which seems to be smaller than mine since I think they all have round butts. There are also the Pachmayr one with different sizes in their own set up (sizes 3S or 2M are the only ones available at the moment) Anybody have an idea of which frame is closest to mine? S&W and Colt, or if you happen to know the sizes of the 3 grip brands well enough to suggest a size. I tried to measure and got 1 1/2 cm for the width of the frame, 4cm with grips. I have a hunch it's a K. Thanks, any info is greatly appreciated!