no clue

[Grubb]

Have found 2 of these now and have no idea what the are. Kinda look like they might have been something like keys you would push for something. Face is about the size of a penny.

 

[Bigcypresshunter]

I think they are some kind of shingle nail.

http://forum.treasurenet.com/index.php/topic,154849.0.html

 

[SkyPirate]

I think they are some kind of shingle nail.

http://forum.treasurenet.com/index.php/topic,154849.0.html

I agree, square roofing nail. SOLVED!