From what I can remember and from the buckles I have; the vintage ones have a sun stamped on the back, the early re-issues have acienox, or something like that, stamped on the back but no sun, and the later ones just have a 'B' on. You can sometimes tell what they are from photo's as the vintage buckle's Heuer shield seems to be a tad thicker and hooks over the edge of the buckle a bit more. Also, the Heuer word looks to be deeper.
Hope this helps.

David Howlett

: I remember seeing a comparison on here but cant find it

: whats the differences??

: cheers