Ok, finally an answer to how springs are attached to the OMS tribe, for those with ADHD short answer is it's jet fin style:
Spoke with Mark at DGX, with his permission here is the answer:
"What you are noticing is one of the differentiators between Dive Gear Express and most other online dive retailers. We use our own product photography in most cases. Most of the other sites use the factory stock photography, which often is not what you will actually get. Those original photos were from of product samples of the Hollis F1 fins that were shown at DEMA by OMS in a huge range of colors, most of which were never actually available in the US from DUI (the US distributor of OMS) and some of which were never even made at all. Ultimately what arrived in the US and we received was the product shown accurately in our own photography was this... (here is one of Lisa's raw photos)"
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