Bob Evans performs a Flip Test with his Force Fins made out a special Tan Delta Polyurethane material.
What do your fins do when you try a Flip Test ?

Force Fins are made of an exclusive version of polyurethane that, besides being resistant to ultraviolet radiation, abrasion and chemicals, is heat-treated for 16 hours at temperatures that would melt other fins. Force Fins won’t wilt when exposed to tropical heat, nor will they harden when ice diving. This special heat-treating process allows the molecules to cross-link into long chains, which gives the material its remarkable resiliency and “snap” or elasticity. This adds to the performance and responsiveness of the fin as it allows it to flex and bend over and over without cracking or fatiguing.
http://www.youtube.com/user/forcefin2020#p/u/12/aUh7K-Ljcwo
Our manufacturing process also results in a material that has outstanding “memory” Force Fins hold their shape in all conditions. In fact, you can take a Force Fin, bend and clamp it in half, leave it for weeks, and when released, it will spring back to its original shape. Try that with any other fin!
http://www.forcefin.com/FF_PAGES/Truth_Dive2.htm

Duration : 0:0:54


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