Pro Teck Thruster Fin Sets are designed to deliver maximum control and performance in most ocean conditions, giving you a smooth combination of stability and drive. The Pro Teck Super Flex Red / Yellow FCS Fin System Includes (1) 7" Fin / (2) 4.5" Fins utilizes FCS plugs and are suitable for all skill levels. That includes you, person reading this and wondering if they fall into the "all skill levels" bucket.