I got the middle size of this board (15" x 20").  It is *huge*. And thick. And heavy. Definitely an industrial strength, professional grade cutting board. The very dense polyethylene is a full 1/2 inch thick. And it weighs an honest 5 pounds. (Yes I measured it myself) It is difficult to pick this thing up with one hand. I should have gotten the smaller one.

That said, this is obviously a very high quality piece of kit. Surely the last cutting board I will ever need :) I have come to appreciate the extra working area of this large cutting board. I like it!