That's a teak deck, and it is laid down over the fiberglass one.
If the boat wasn't designed to have a teak deck initially,
then adding one after the fact will negatively affect its stability, as it adds a significant amount of weight and shifts the center of gravity up.
Also, if it was installed in the traditional manner and the boat has a cored deck, you can be in for a very rude awakening, since the screws that hold the teak to the cored fiberglass will often lead to large areas of the core getting wet and either delaminating (foam core) or rotting and delaminating (balsa or marine ply core).
While there are a few boats in that range have teak decking, but most are boats I would personally avoid if I were looking for a monohull. A small monohull has no business having a teak deck IMHO, since it will suffer a disproportionately high penalty in performance for it.
Besides, I kind of like the no woodwork on deck since I prefer sailing to varnishing, sanding or maintaining teak...

__________________
Sailingdog
Telstar 28
New England
You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.
—Cpt. Mal Reynolds, Serenity (edited)
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