I read a thread on fatwallet.com and bought a 3" tempurpedic top cover for $120. 10% off, $1 shipping.

I like mine alot, it was so large I folded it in half and have a 6". It isn't really good for sex but for sleep its awesome.

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I bought the tempurpedic top cover for $120 from overstock -- fatwallet.com gave the 5% cashback and 10% off, $1 shipping.