[Fatelvis]

I think this is to a revolver. Can you help me to identify the brand/model? Thanks-

[Gordon]

Is that a King Wonder Sight ?

[Fatelvis]

I dont know, but Im thinking it would be great for silhouette shooting!

[Bullet Bob]

It's not a Wondersight, but I'll be dogged if I know what it is! My best guess is that it goes with one of the ribs like Aristocrat or others that people used to put on revolvers for PPC, etc. I'm basing this guess on the elevation screw shown.

[slopemeno]

I would guess a Diana Airgun if some sort.

[JohnKSa]

Looks like an airgun rear sight to me too.

[Sheldon]

Gamo brand air rifle sight maybe??

http://www.gamo-airguns.com/fotos/delta_rear_sight.gif
http://www.gamo-airguns.com/fotos/milimetric.gif

[Fatelvis]

Ahhh, I think we have an answer! Thanks Guys, I was hoping it was a centerfire pistol sight. :(

[Sheldon]

What model revolver are you looking to change to an adjustable sight?? I have read a few threads along that line over on the http://smith-wessonforum.com/eve and depending on the model S&W revolver it maybe cheaper to sell the fixed model one and buy the adjustable version. Specific mention of the S&W 681 and 581 were made as fewer of them were made compared to their adjustable sighted counterparts, the 586 and 686, and as a result carry a premium.