This device is US$310. Good carbon fins (the long ones for freediving) cost just a tiny bit more [1] and can also propel you at a superhuman speed. Plastic ones

This device is US$310. Good carbon fins (the long ones for freediving) cost just a tiny bit more [1] and can also propel you at a superhuman speed. Plastic ones are even cheaper. A speed comparison would have been nice. EDIT: it's already there: "This jigger, according to the manufacturers, makes you handily quicker than an equivalent swimmer with fins on." [1] https://www.westmarine.com/mares-razor-carbon-dive-fins-41-16367542.html https://www.westmarine.com/mares-razor-carbon-dive-fins-41-1...