The American Pro II fretboard looks pretty slab to me.
As this is the default for Fender since they changed it back from the round laminated boards in the early '80s, I believe they didn't bother calling it that anymore. Maybe out of fear it could be regarded a downgrade from the round lam?
I guess the use of the term for the Player II series has its origin in Fender's marketing department looking for new ways to describe the same old thing and making it sound more vintage inspired.
The term 'slab board' is usually used with vintage instruments from the time before Fender started using round laminated fretboards in the early '60s. Accordingly, the only other current bass I know where Fender explicitly specifies a slab fretboard is the American Vintage II 1960 Precision Bass.
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I had checked with Fender Customer Service they told me laminated rosewood board on the Professional ii.
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