These little kickers are designed specifically for bodysurfing and damn do they work well. The blade is the perfect size and has a great flex for quick sprints. In addition the fins have little built in vertical blades to help stablize the fins and keep you in the pocket. Hands down the best bodysurfing fins out there. These fins run really small, so you might consider ordering a size up. The sizing is: Small 3-4, Medium 7-8, Med. Large 9-10, Large 11-12, and X Large 13-14.