FCS II Skindog Performance Core Side Byte FinSide byte set produced in collaboration with UK longboard champ Ben Skinner. Designed for the Skindog 2+1 set up. Ideal Conditions Open face, down the line waves, particularly good in point and reef breaks. Board Types Designed to fit the FCS II Fin System. Suitable for longboards, SUP's or as shortboard quad rears. Fin Family Carver: Find Power. Powerful, drawn out turns with added hold.