I got these the other day because my biking shoes were getting wet and starting to smell mildewy. I tossed these in the shoes for about 2 days and it helped a lot. There is still a tiny bit of mildew smell if you really put your nose to it, but for the most part it smells a lot better. Although, now it just smells like laundry detergent.

I have two minor complaints about the product. One, I wish they had a better scent, not just strong basic laundry detergent. And two, the do not want to be put in the open position. When you twist them open there is no physical lock for the open position, but you can twist it either way to close it, which seems to lock in that position. So you have to carefully fine tune how much you twist so that it stays in the open position and doesn't just snap closed. Not as easy as twist and toss.