Tusa X-Pert Z-3 Zoom Split Fins

I have a pair of rocket fins I bought on a leave from my three tours in vietnam.Used them in the South China Sea,there great. I have another pair of blade fins Sea Elites,I bought in 1981.But for open water diving I want my Tusa's.I have tested and compaired all three pair.For tech diving I like my rockets in tight places and less space,I feel better control.But deep diving,drifting and unconfined spaces I wan't my Tusa's.There is less fatigue,and powerfulstroke.At same distance the finning stroke has blade fins.The tusa took 5 less finning strokes