Those could be Revere, don't know the exact model though.

I agree with Vince...I have never actually seen those stamped version!

I like stamped clamshells better for some reason

i like all Clamshells,though Cast one's are obviouslly more durable,i imagine a hailstorm destroying Stamped clams?

yeah. The cast ones will hold up better. Stamped ones look better IMO.

What's the difference between Stamped and Cast?

you've got to be kidding.

Ian, stamped clamshells are ones with an external reflector like these. A cast clamshell is just that: a cast housing with an internal reflector, like most OV20s.

Great explanation Michael!!! However the GE Form 400 were stamped clamshells with internal reflectors too! But you are correct in general. The Stamped OV-20s which I have has the external reflectors, same goes for the GE Form 175, and the OV-10......

So in general not ALL of the stamped clamshells had only external reflectors...some actually had internal reflector! Not sure about those, but looking at this pic, it's hard to see but it may have an internal reflector...

Hmmmm. My OV10's stamped part IS the reflector......

That's what I said...but not all them.....the Stamped OV-20, the OV-10, the Form 175 I have the stamped part is the reflector.....but my Stamped GE Form 400 has a separate reflector! Look in my link above I added more explanation...

i misread your comment. anyways, Yeah the one you linked probably has an internal reflector because the socket is street side. I thought street side sockets were a more modern thing...

The Form 109 had a street side socket!