Kryptonite's keyless wheel nuts use gravity to provide security without any added keys or tools.
Once installed - with a standard 15mm wrench - the nuts can only be removed by flipping the bike 180˚ upside down.
Bike right-side up = locked Bike upside down = unlocked
The idea being, when your bike is locked up properly, it can't be flipped over. However, if you need to remove a wheel, you can easily remove the security bolt with no tools. Security with nothing to forget or lose.
Standard M9 threading for bolt-on FRONT axles only. Lifetime warranty.