Hi jeorge
There are stickys that explain both.
PDT is premium dedomed tint. Vinh selects the best led with the best tint.
Fiat Lux is the best of the best.
Vinh will build a batch of lights and the best light of the bunch may get the Fiat Lux raiting.
Sorry quick explination.
Still not feeling good
Ty
Ok, thanks.