Speed & tight turns. Ideal for beach breaks. Overview Designed for speed and tight turns, with added tail release. Upright template allows for tighter, more acute directional changes. Smaller centre fin for increased pivot and tail release. Ideal for surfers who like to perform fast, progressive turns. Ideal Conditions Suitable for hollow waves, particularly good for beach breaks. Board Types Designed to fit the FCS II Fin System. Recommended for performance shortboards with moderate-to-low rocker. Fin Family Reactor: Find Speed. Speed, tight turns & snaps. Performance Core Performance Core (PC) fins are made using a multi-layered resin transfer molding process. The flex pattern in PC fins extends progressively from the base through to the tip, helping the surfer to maintain drive and hold through a turn. This versatile fin material is light, and can be used in a variety of different conditions.