I just returned from a fishing trip and saw the posts made by you guys. Sorry for not being more "specific" I didn't know about any difference. I bought them several years ago but never actually got to use them because I tripped and tore the cartilage in both knees. Subsequently I developed nerve damage in both legs because my system evidentally wasn't absorbing Vitamin B-12 from the food I eat. I never really learned the serious part of float tubing and therefore don't know everything there is to know about Force Fins. Again, please accept my apologies. Anyhow, they are the older type illustrated at the bottom of Normand's post. When I bought them I believe they were the only version of the Force Fin made.