New and Sealed 3/8" Axle Nut.Gravity locking system attached to your front wheel.Easy installation - requires only a 15 mm key (without keys).WheelNutz provides an internal LOCK-OUT function" and can only be dismantled by turning the bike 180 degrees.Weather protective coating keeps WheelNutz from corroding.Once installed bike must be turned upside down to remove it.Fits 3/8 axle thread only.