the middle mouse tub 1/4 harware cloth and the top and bottom with ASF's 1/2 inch hardware cloth but curious as to will the offspring be able to get out of the 1/2 top even with it roughly 11 in overhead. And yeah Rhasputin i did actually, i think i got the washer idea from one of your previous post so when i went to work next day i snatch up some with variable sizes, i work on helos so we keep tons as easy accessible consumables .