Having several Hinault Turbo saddles on several bikes, I checked to see if any contained the date code wheels on the underside of the shells. Only one contained a date wheel, and the year is 1988. All of the other do not have the date wheel. Seem to recall that my first Hinault Turbo was purchased and mounted on my Gios Super Record around 1984. Always assumed that the "suede" type Hinault Turbos were made of buffalo hide, as they have almost the same texture/feel/appearance as Unicanitor #3s once ridden.
Also once owned a white "Special" or "Super" Turbo (???) with the clear plastic front nose and rear rail covers over the world champion decals. Really didn't like it only because the decals tended to move/crinkle under the plastic covers. Only an appearance issue, as I always have found Turbos to be an extremely comfortable and durable saddles.
As for the SLG models, my experience is that this mark indicated the alloy rail version. For what it's worth, hope this helps.
Regards, Kevin Kruger - Grantville, PA
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