Thanks both for your advice. Ultrasonic carbon is ordered

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Would the 58 fin be Ok for the 9,2 H2 ? For the 7,7 hellcat a 52 or even 50 might be suitable ? Apart from the Drakes or Deboichets - does anybody have experiences with other fins, e.g. select or mfc for the ultrasonic.
I would be happy with a recommendation.
Regards