The tri-chrome extension attaches to the trunk helmet holder latch making it easy to hang the helmet when not in motion or when there is not room in the trunk. It slips through the D-ring on your helmet to make it easier to attach the helmet to the helmet holder latch under the trunk. A more convenient way to stow the helmet. Measures 4 inches long and 1½ inches at the base. Made for the Nolan helmets. Pair.