The Kai R2 quad set is very similar to the all new KAI XXL R2, but made to be riden in normal surf conditions. The rear fins have the same outline and size, but with an inside flat profile and faster draft position. The front fins are smaller on the outline than the XXL R2 but also have an inside flat profile. We found this combination very fast and very easy to control. The constant flex of the rear fins allows for good turns while keeping high speeds.