We've had some users who have needed a longer strap when wearing rock boots or something, and the medium heel strap was not long enough. This heel strap extender seems to work well, and one may be secured to a fin post, or to both fin posts if necessary. It eliminates the need to buy a longer strap, and this thing should be cheap. Anyway, we might mold something like this and make it available to those who have fins with the large posts, such as truefin. These were just 3D printed out of glass filled nylon... Unless the scuba industry is asleep, this should already be available somewhere, but I can't find any,, so if anyone knows of this existing already please let me know, I would rather not have this molded if it is already out there.