I hope you haven't purchased one yet cuz I found a fabulous one!!! It is 18"x24" and the mat is replaceable!!! It is really thick and doesn't wobble. I have a round and square ones and this one is the best. The plastic is super thick - 3/8". I found it at the Jacksonville Quilt Show 2 weeks ago and I've have used it to death! It is made by Bebas Enterprises in Gainesville, GA 770-712-5000. They also make cutting mats that are at least double the thickness of any I have ever seen. A friend got a huge one that covers her entire cutting table (larger than 8'x4') for about $160 and it is super fab. This is where I will be getting all my cutting mats in the future.
Thickness of plastic
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Large lazy susan on bottom
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Top of rotating Bebas Mat
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