I use these pads from Sams Club...
Sam's Club - Member's Mark® Comfort Shape® Underpads - 120ct
And sit them on top of this tray, its a perfect fit!
Amazon.com: Replacement 8-Pan for Midwest Life...
It is so easy to clean, just wipe down tray.
I am interested in using the Walgreen ones, they even ship for free. I was just wondering if you put them straight on the floor or do you use a tray as well. I can't find a tray that would be the same size...
Thanks!