The Solution is FlatLiners: shoe deodorizers.
Unlike other inserts, Flatliners are specifically made thin enough to use in women’s flats. You never have to say, "my feet smell"; again thanks to these little activated carbon helpers. They can be placed in already stinky shoes or in new pairs as a preventative measure against stinky shoes, extending the life of your favorite around-town shoes, heels, flats, and everything in between. Flatliners have self-adhesive strips so you can simply peel and stick. If they happen to get "fuzzy" just trim off the fuzz from that white layer; the carbon is under that so it will not affect the efficacy. Flatliners should be changed about every 3 months or 3,000 miles, whichever comes first, to keep your shoes smelling fresh. Flatliners are made for everyone: women, men and kids and will probably not cover your entire insole. They are designed to be placed into the toe of the shoe, when most of the odor resides.
Using Flatliners is as easy:
1) Wipe out inside of shoe to remove anything that might interfere with adhesive.
2) When dry, peel off paper backing and adhere flat liner to the inside sole of each shoe.
3) Replace flat liners every 3 months or 3,000 miles, whichever comes first.
Contains: 1 pair
Material: Soft fabric-covered antimicrobial activated carbon
Measures: 7 x 2.9 x .04 in (17.8 x 7.4 x .1 cm)