FCS 2  Fin Plugs are for use with FCS II fins and 2 tab, FCS 1 fins. FCS 2 Fin boxes are perfect for shaping and repair. They are available in black and white and offer 5-degree and 9-degree options. 
 
Purchase options:
To buy a full thruster set, choose your side angle and select the 0-degree option (best for shapers)
For just the side boxes, they come as a pair left and right, and select without 0-degree option (best for repairs)
and confusingly if you just want a 0 degree select 0 degrees without 0 degrees, unless you want 2 haha!