To Remi - on Formula R20 fin

hi remi,

thank you for reading this thread.

i'm looking for a nice fin and read about your R20 recommendation.

i'm using a 161 and 162 boards at the moment.
my place blows from 5-16kts but less than 20 kts with small to medium chops of wave.
occasionally, i race in Formula races as a novice.

i am 78 kgs and using 10.7 - 11.8m sails.

Which specs should I order ? (rake angle and stiffness ?)

any other comments will be good.

thank you again in advance.