In the meantime or while you are looking for another expen you can protect your wood floors by using a piece of linoleum. I bought a leftover piece of linoleum from Lowes or Home Depot and cut it to be just slightly larger than my expen, then covered that with a blanket and put our expen on top of the blanket. This setup works great, the floors are protected, and I can wash the blankets as needed. And, I didn't have to spend more money buying an additional expen.
Teresa