From the rule book
Rudder blades* and rudder assemblies** shall
be stock as supplied by the HOBIE CAT CO.
Only Hobie Cat Company supplied aftermarket
rudders* are allowed to replace stock rudders.
* Defined as Hobie Wave and Hobie 16 rudder
blades.
** Defined as the original Hobie Wave system
and the Hobie Wave EZ Loc system.
NOTE: As of the time of this writing (February
2010) only aftermarket rudders are available
that fit the old style rudder castings.
the pre EZ Loc rudder system (original to the Wave)
is the same casting as H17, H18 and H20
long story for YES