It is a model of S&W small .22 cal.....to "go in your kit", like in your fishing kit or
hiking kit- small & light. Usually a 3 or 4" bbl light revolver, I think all are/were in .22 cal,
but perhaps some in .22 Mag or .32, but I never saw one like that. I think they all have
adjustable sights, too. On the small frames, too.
https://www.smith-wesson.com/firearms/model-317-kit-gun
Current iteration, have been many variants over the last 50-75 years.
I have one of these, and it was not called "Kit Gun" when I bought mine about
10 yrs back, it was just a 317 AirLight .22. And it weighs about 9 or 10 ounces, and
as Al said - makes it hard to hit with. Also the silly sights were really a PITA, had to
change them out. Front was a round topped fiber optic ---GRRR. And the rear blade
had a V-notch. Changed the front to a flat topped fiber optic and the rear to a square
normal S&W blade. Easier to hit with now, but the low weight is still a hinderance for
shooting accurately, but a delight to carry around.
Here is a pic of an older model Kit Gun.
https://s3.amazonaws.com/mgm-conten...92516_01_s_w_model_34_1_22_32_kit_gun_640.jpg
Bill