I've used both. Started out with disposable ones....but, when the new pups started shredding them and I had to pull fuzz out of their nostrils with tweezers I switched to the washable ones. I wash them in cold water with detergent and biz.....spray and wash to get poop stains out. About every fourth washing I'll use bleach (bleach does tend to rot out the plastic backing) just to disinfect.......throw them in the dryer.....it is recommended not to use fabric softner.
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