Sand sifts out from the top and can't come back up from underneath.
Brad's Deals Editor Chris,
This Sand-Free 5' x 7' Beach Mat, listed at over $50, is now $20.99 at Tanga. Use our exclusive coupon code BRADSDEALS during checkout to save another $2. Plus it ships for free, making this the best price we've ever seen, and the best current price we could find by at least $5. It features one-way construction that sifts sand from the top and out the bottom, but doesn't allow sand to come back up from underneath. It comes in three colors. Sales tax is charged in most states.