The Ana Leaf Corbiere Duathlon is a Run/Bike/Run event of various distances:
LONG (15km of running, 40km of cycling),
MEDIUM (7.5km of running, 20km of cycling) or
SHORT (5km of running, 10km of cycling)
The cycling component is non-drafting in all cases (TT bars and disk wheels are allowed).

Full instructions will be sent to you a few days before the event.  Be ready for an early alarm call.  You need a road worthy bike, a helmet and clothes/shoes suitable for running and cycling.