PC stands for Performance Core – basically a light fin with fiberglass feel. They are some of the best FCS fin’s I’ve ever used. They won’t track like big fin’s have a tendency of doing, and have great drive and release.
FCS makes a scaled down version of the K2.1 PC called the K2.1 Grom, for young surfers and surfers under 120 lbs. Another great small FCS fin for grom’s is the TP-G – if the K2.1 PC feels to wide for your weight. The TP-G is a scaled down version of the original Timmy Patterson template, which is an all around perfect fin for every kind of surfing.
Only time I don’t recommend using the K2.1’s are when the surf is over 6 feet. When the surf gets bigger I’ll plug in a longer fin like an AM2, so I have more control off the bottom and in the barrel. For everyday surf the K2.1 is an incredible fin.