peep sight?

I hope this is the right place for this; I got 2 old peep sights that were my Father in Law's that I don't know what they fit. One is a Lyman and the other I'm not sure. The one that I'm not sure about has a rounded side and the lyman is flat. If this is the correct place to ask, I'll post a picture.
Thanks.

They sound like receiver sights, one to fit a flat frame like a lever action and one to fit a round one like a bolt action.

Sometimes a code number is stamped on the inside surface, which tells what rifle the sight is supposed to fit. Often, however, this mark is ground or filed off in order to make the sight fit better, or fit another gun.

By all means, post photos.

Attachment 217556
see if this works

It looks like the bottom sight is a Lyman 48, and probably for a 03 Springfield. It should have the letter S stamped somewhere,mine is stamped on the flat just beneath the rear screw hole, the hole covered by the slide. The front of the sight will have a knurled nut that you loosen, then depress and the slide can be quickly adjusted or removed. Also, if for an 03, it should have a small circular cut on the top of the base to allow clearance for use of a stripper clip. It should have the Lyman running deer trademark on the slide, and graduations to 125. A very desirable sight you have, did your FIL also have a nice old 1903 Springfield?

Thanks, my Father in Law was a "collector" of things, he didn't have a 03 Springfield that I knew about. He could have had one at one time, but he would buy leftover estate sales from a Local Sporting Goods Store and I think that's where it came from. Its does had the small circular cut, the running deer and the 125 yard graduations. I haven't seen the S yet.
Thanks again.
Frank