The first attempt was thwarted by the Cressi with Aussparrung for the toes, this was too close to the toes and pressed too hard against the low end peep big toe. A number greater than the fin were too large. Aqualung fins La Costa Fins Deluxe had Plan B and would plan to be A. The recess is wider and earlier so make at 38-39 and 40-41 the toes no problems.
