The Thule Thru Axle Syntace Adapter replaces the 12 mm Syntace rear axle on your bike. This allows you to attach a Thule ezHitch so you can tow a Thule child carrier or multisport trailer. It works with the Thule Cheetah, Cadence, Chariot or Coaster trailers and is simple and easy to install. It is 12 mm in diameter and for use with 160-172 mm length Syntace axles with a M12 x 1 mm thread pitch.