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...so there is additional cost involved, unless of course your getting a replacement cover from Doc, he has a multiple of colors to please and satisfy.
I just ordered my Sundance spa last weekend and got the palamino color cover. It's a multi-tone tan cover that has a darker tan color than the birchwood surround and some color that matches the birchwood. In my opinion, it goes very well with the birchwood....much better than the standard redwood color. The dealer had about 10 upgrade colors (including the palamino color) that you could get your cover in for about $100 more...
...BTW, ozone really works better when it is understood. Mother Nature uses it exclusively, and without chemicals.