The design, “the twin fin” is an oldie, but still one of the best surfboard designs ever! I recommend every surfer to at least have a go on a Twin. It does amazing things for your surfing, teaching you to use your rail properly as well as showing you different lines you can take on a wave and the different power pockets to use. They were a great design in their day and still stand as one of the greats. On a rail you have speed and drive, but when flat, oh yes you can slide!