GT Layback surprise

I have a yellow layback seat post that I bought a few years back but never used on my GT performer build, since as I used the NOS white GT one I bought from Earlsstuff.


The yellow post had a GT decal and looked completed unused. As I couldn't see any markings or stamps on it, I assumed it was a knock off and since then it just gathered dust. Comparing it to the NOS white post I have, they looked different too, the bend was roughly the same, but the end of the seat post differed. The NOS white one had straight cut ends, while the yellow one was rounded. Anyway, I though for the hell of it I'd get the "knock off" post refinished white, so I removed the decal and through I saw a possible faint outline of a GT stamp....

A bit of paint picking later it turned out have the GT circle stamped, with CA CR-MO 4130 under the circle stamp.

       GT
       CA
CR-MO 4130

At the lower when of the post I also saw it's stamped

 ------------
   INSERT
 THIS LINE
   JAPAN @

"@" is a baseball symbol.

Also under the yellow paint and traces inside the seat post tube the Seat post is completly orange. Not day glow, but a normal orange, and no idea if that was the OG colour.

Earlsstuff has a nos 1985 white one for sale at the moment out of a GT world Tour bike kit and it has exactly the same markings.

Some pics of my post:

GT Circle stamp:

"Insert this line" marking:

Orange paint: