Using the 6' JJF Pro Leash on an 8'10" stand up paddle board/wind foil board is probably not what JJF had in mind, but for me it's the perfect length for flat water paddling (I haven't surfed it yet.) It's light and comfortable. There's minimal but just enough drag to keep the leash from getting underfoot when I'm doing buoy turns and free style spins, especially when I switch from goofy foot to regular foot and back. It's also short enough that it doesn't catch on rocks, submerged branches or other navigational hazards. I'm stoked to try the 9' calf leash for ocean paddling/surfing. Great product. Highly recommend.