Apollo Bio Pro

The Apollo Bio Pro is made from natural rubber, which is the very best fin material in the world. Brilliant new technology gives extra speed and strength while virtually eliminating muscle cramping. Excellent for weak swimmers. Split fin technology makes finning easier which reduces your air consumption. Fantastic power and speed with little effort. Black Only.

These fins have a large fin pocket but as an estimate; 
XS - SM 6/8
SM - MD 9/10
MD - LG 10/11
LG - XL 12+