So many questions about this, so I made a post about it not too long ago with two of what seem like the same board, but obviously are not. From my post:
Difference in concaves from I to IV in the press.
So I have two Antihero eagle 8.38 decks from the same woodshop (BBS) to compare and pretty much the same in every way, but one is from the top of the press, the I with the yellow and green ply, then the other is from the bottom or last board in the press, marked with IV and has a blue and grey layer. They both have orange tops, but the different other colours make them easier to tell apart.
The top board is much steeper overall in both concave and the angle of the kicks, as well as being a tiny bit longer overall too, which is interesting to note. These boards are all pressed and cut with automated machinery for the most part, so the angle of the kicks does ever so slightly change the board as part of that process.
To stand on them, there are significant differences between the two and although I prefer the more mellow bottom boards, I can still skate any of them easily enough, but it takes longer to get used to the I or II decks, than it does the III or IV decks.
Most shops would never advertise what number the boards are, so if you are after a specific number, go into the shop to see for yourself and stand on the board, or ask so they can check, but quite often they will not know what you are talking about unless they are aware of the product differences or are into such things.
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