What you see in the pic is a 1958 vintage Old Model Ruger Single Six in 22 LR with a 5 1/2" barrel and the original black rubber grips. This was a couple of years prior to Ruger shipping extra 22 mag cylinders with the Single Six, so the bore is the true .222" 22 LR bore size, instead of the later .224:" 22 Mag bore size. It's in good shape, not shot much, more carry wear than shooting wear.
As mentioned, this OM Single Six has the factory Ruger rubber grips, but this early version has the older XR3 grip frame, which was changed starting sometime in 1962, so these original early grip frame grips are now quite collectible, bringing $100 or more if in good shape like these.
This one will be my OM Single Six shooter to save wear and tear on my later 1965 Single Six is in like new condition with box and papers. This earlier vintage was also prior to Ruger offering adjustable sights on the Single Six, so it has fixed sights, though the rear blade can be adjusted for windage. Still an improvement over the typical Colt style fixed gutter sights. Should make a great Single Six plinker and fun shooter.
