I didn't know this until just the other day, thanks to my sister-in-law. Walmart.com gives lots of free samples of selected products so you can try them before you buy them. Click here to see whats available now. I know they have Crest Whitestrips right now, which, from what I've heard, are kind of expensive. So hurry! Unfortunately I couldn't find any samples that would ship to an APO address.
2 hours ago