I have a wonderful quilted fake lambs wool mat (about 2-3 "thick)and I wash it often! Unfortunately I can't read the tag! I have seen these around BUT I would make sure it has much stitching so it holds together as well as mine which I've had for at least 3 years! You could also just buy the fake lambs wool sheet and cut it to size...I use these also so it would depend what you want. The lambs wool holds up equally as good and I like the soft,furry feel!
I'd avoid plastic foam. Any thick, fluffy old rag or worn-out blanket should do. Why wash it? That just ruins its delicate patina of stink, and a dog might well find any scent from laundry detergent very objectionable. I occasionally throw the bedding in a hot fryer for 15-20 min. to kill fleas and eggs or wool moths, and vacuum out the crates.
Hey, I know they wanna be treated like royalty, but it ain't Buckingham Palace. :)
I couldn't find one with a removable cover so I am making one. All the ones I found either had fake fur on them which Finn will eat or they were too thin. I've been using old towels until I can get the crate pad made.
I bought a fake sheepskin when I got the crate, it was made to fit the crate we bought, is totally washable and is light enough for Archie to do his "housework" (moving it around til he got comfy , especially in the summer when he preferred to lie on the cooler crate floor.
Petco sells one that is a foam egg crate 3 in. thick with a brown zippered cover; fuzzy on one side and smooth faux "microsuede" (is that even possible?) on the other. The "fuzzy" is not the fake fur nubbins, but a short, smooth fuzz. Like an earlier comment by Alice, Max eats fake fur. I have washed the cover a few times and it holds up great, but I have not put it in the dryer.
Also, my Max liked to nibble off the egg crate "mountains" right through the cover. Kind of a latch-and-pull tactic with his teeth. So I unzipped it, flipped it so the egg crates are on the bottom but the fake fuzzy is on the top, and put it flat-side-up in his crate. My theory is it still has the benefits of egg crate goodness (whatever that may be) but he can't get to the foam "mountains." Clear as mud?