It’s simple. Flat-out are anti-puncture inserts that will save your butt. Sooner or later you’ll be riding with an insert anyway. Now it depends whether you overpay for marketing or not. There are no miracles. Each insert is a piece of polymer that is designed to stabilize the tire and protect the rim. In terms of quality, cheap inserts are sometimes at the level of an expansion hose, and the more expensive ones simply drink less milk and have funny colors…

After thorough analysis and tests among leading Polish gravity cycling enthusiasts, we can confidently say that FLAT-OUT inserts will not break and they do the job.