Two Mares Fins: The Volo Power is still strong and the next gen X-Stream is high tech

Your impression of new pair of scuba fins, be it good or bad is completely enmeshed with what fins you had before. Be the question: “What are the best fins?” or “What fins should I buy?” or even, “Are these fins any good,” the answer is always “it depends.” Even if Spock could scan you with a tri-corder and tell you the perfect fin for you, it would still be good chance you may not like them for the first 10 or so dives. This is all to illustrate that fins are one of the hardest categories of scuba gear to evaluate. With dive fins, subjectivity is the rule.

Mares Volo Power Open Heel Fins Yellow SmallFin manufacturers have come up with all kinds of formulas and mechanical devices for testing. But in the end the question of the right fin is still no easier to answer than, and has a lot in common with, the question “what is the best shoe?”

In this article we chose to look at a small but delightfully interesting piece of the fin pie illustrated by these two related fins from Mares. First, the well loved and from our perspective, surprisingly under- respected Volo Power fins and second, its next gen, high tech offspring; the X-Stream.

Both these fins are in the pivoting blade category. This category lies in between split fins and blade fins on the spectrum of power. These fins are both recognizable by the what looks like a handy finger hole at near the foot end of the blade. While it does come in handy as place hold the fins, it is in fact an integral part of Mares patented OPB (Optimized Pivoting Blade) Fin Technology that ensures the blade is always at an optimal angle during both the up and down stroke.

Even though the Volo line has been around for quite a few awhile my interest in reviewing these fins was sparked when I noticed I had to kick a bit harder to keep up with dive buddies who were wearing Volo Power fins. As soon as I had a chance to test a pair of Volos, I learned why Volo users fall in love with these fins.

The Volo Power fins confront a failing of split fins. When split fins came along the rocketed in sales because the offered recreational divers a way to move around with ease. Splits get you moving with almost no feeling of resistance and or the “burn” you feel with stiff paddle fins. However, divers became concerned that split fins would not be powerful enough or safe in currents (except the Foil Force Fin). Some manufacturers added stiffeners or made other modifications to their split fins to try to increase power.


imageMares O.P.B. (Optimized Pivoting Blade) patented technology allowed for a new category of fin that retained the ease of the split fin but grabbed power from the paddle fin design. The optimization part of OPB is a little trick that prevents the fin blade from pivoting too far and causing drag. During the finning cycle of a traditional paddle fin a large portion of the fin blade can push the water up and down, instead of rearward as thrust. The OPB system ensures the blade is always at an optimum angle and providing maximum thrust during the full upward and downward strokes.

Channel Thrust Technology

Channel thrust technology, also a Mares patented feature, prevents water from spilling over the sides of the blade where its power is lost. The result is greater thrust with same amount of effort than other fins with same blade size. OPB, combined with a these water channels is what gives the Volo the power to zip you along with unbelievable ease and extra push to handle currents.

Enter X-Stream

The X-stream is an the next evolutionary step up for OPB. It expands on the Volo. But it does not make the Volo obsolete. The X-Stream model gives divers another choice by stepping up OPB to “next generation OPB.” This ostensibly means that the OPB pivot point in the X-Stream is now at the foot pocket providing a larger surface area of thrusting blade. Additionally, Mares incorporates many subtle features to increase efficiency. In both form and function, this is truly one of the highest tech fins on the market. My first impression was about how this fin reminded me of high tech running shoe. After diving it, I am even more impressed that it was equally well designed and the tech was not just in the look. Besides removing all the parts of a the fin that do contribute to thrust and pure function, the X-Stream is the only fin on market that prevents drag from the “parachute effect.” The X-Steam is a refreshing light fin as well and easy to carry and manage on the surface.

As you swim forward, the foot pocket on other fins can trap water and cause drag like a parachute. This effect increases the more space you have around your foot in the pocket. Mares designed the X-Steam foot pocket and used materials to make the fit better and then perforated the pocket with holes to allow any water that does enter to pass on through.

A nice side effect of the foot pocket design is a fin that is very easy to doff and don. Wearing a pair of Oceanic Vortex V12 split fins, I recently spent time flopping about in the water while my buddy tried to break the suction that had my boot trapped in foot pocket. The X-Streams always just slide right off. It makes me wonder if I could drill some holes in other fin pockets, but I suspect their would be unforeseen consequences.

On the first dive I also became aware that, more than any other fin I have tried, the X-Stream felt like they were an integral part of my body. I also found that I enjoyed extreme control with these fins and could make delicate maneuvers and frog kicks with ease. However, unlike split fins and the Volo Power fins, with which you move with little experience of doing work; X-Streams are more like a power paddle fin in that you will “feel the burn” (mostly in your calves) when kicking with force. Neither experience is negative. Evidenced by the longevity of classic rocket style fins, there are as many divers that prefer to feel the power of the kick as there are that like to stroll along with ease.

As with my experience, other divers that have tried or dive the X-Streams report that it took 5-10 dives with the X-Stream fins to grow into appreciating them. One Volo user was at first convinced the X-Streams were not moving him along as well, but after a few more dives he could see that they were in-fact more powerful.

A few quotes on the X-Stream fins…

  • It was nice to be able to firmly grasp them both with one hand while trying to fight the tides getting out of the water on a really rocky exit. I was looking specifically for a lighter less bulky fin for use when travelling but still met the demands of various ocean conditions. So far I am happy with them. (Piccola ScubaBoard)
  • Find them a lot easier and faster to catch up to other divers if finning slowly on them . Saw 2 divers racing each other one with volos and the other with the x-streams . Out come x-streams won by a long shot . Well done to Mares on making a nice light weight fin that are good for travelin and supper fast in the water (chrisgp007 – ScubaBoard)
  • I actually like them a lot better. They did not hurt my knee at all and that is a major factor for me. I had great control for camera work and I could actually move in revers a lot better. I did play a bit, spinning in one place, ETC. all worked great. (Armistead Lucas Coleman)

Clips and Straps

The tech does not stop with the fin body. Mares also has a patented buckle system. Unlike other straps that you must tighten by pulling the strap after you don the fin, the Mares buck allows you to pre-adjust your strap, don the fin, and then easily snap the assembly closed. Another advantage of the buckle design is that it allows you to open the buckle and slide the strap over your wrists with exiting the water. This leaves both hands free to climb a boat ladder, hold on to a camera, or prevent fin loss while in the a surf zone.

Unbuckling ease depends on what you are wearing. No glove or thin gloves are no problem. For all but the few and true cold water divers, the buckle system is easy to pop open again by squeezing the release buttons. However, for those divers wearing thick wet or bulky dry gloves this is not so simple. In those cases Mares recommends replacing the straps with their spring straps. Those cold water divers we interviewed that made the switch to spring straps have been pleased.

This issue illustrates how “forum grumble” can spread and give a false impression of a product. The grumbles we heard about the buckle system not working for cold water divers lead people to say that Mares was not thinking when they designed the buckle system. But when we interviewed Steven Lamphear at Mares the choice was clear and logical. He explained that they decided it was much better to make a practical and affordable buckle the works well for most of the divers and then offer an option for those few than need it. In nearly every instance, when we hear divers complain about a product and we take the time to dig for the “deep background,” we find that the scuba equipment designers have thought though and tested their products thoroughly and there are usually compelling answers to a diver’s grumble.

Bottom Line

We have had a great experience getting to intimately know these two Mares fins and have a developed a respect for the Mares design team. Our original hypothesis about the Volo Power fins was validated. After years on the market, and somewhat under-appreciate, the Volo Power is still an amazing fin for today’s diver divers that want zip along almost effortlessly and have reserve power to handle some currents.

The leading edge design of the X-Stream raises the bar for high tech fin design and provides a fin that feels like it is part of your body and offers full power and delicate control while being light enough to double as a travel fin. As reporters we are constantly judging companies as to where they stand on the value-price ratio. Mares continues to hold its high position in our experience. It is a company that offers the great value through products with expensive, elegant and high-end design for an affordable price.

We extend our special thanks to Karen Flood and Steven Lamphear at Mares for answers and arrangements. We are also grateful to the staff and divers from Exotic Aquatics, on Bainbridge Island, WA for their help with testing and interviews.

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