It is called the Flat-D Flatulence Deodorizer and is worn inside your underwear. The disposable pads come in packs of ten and cost a whopping $30. They can be used daily or whenever needed and work with almost any kind of underwear except boxers and thongs. You attach double sided tape to one side of the pad and stick it to the inside of your undies.
They aren’t flushable and you can buy the reusable kind or the disposable kind. The reusable Flat-D Flatulence Deodorizer costs $14 each. After use, you just wash it and it won’t lose its odor eliminator. They can also be cut to size with scissors. They also sell a Flat-D chair pad. It is washable and reusable.
When you pass gas, the filter in the pad absorbs the odor and no one has to know what you’ve done. See a pic of them here