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Frequently Asked Questions

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Q: What will the DOL-Fin do that no other propulsion device will do, and what does it do better?

Q: When can I purchase a DOL-Fin?

Q: How is SCUBA diving with a DOL-Fin different from regular diving?

Q: Is it difficult to learn to dive with a DOL-Fin?

Q: Does the DOL-Fin fit in a dive gear bag?

Q: How fast is the DOL-Fin?

Q: Which DOL-Fin is right for me?


Q: What will the DOL-Fin do that no other propulsion device will do, and what does it do better?

A:  There are multiple answers to this question.  However, all DOL-Fins share a common characteristic that is very important.  All DOL-Fin models offer a significant improvement in comfort and provide efficient low stress / low energy diver propulsion.

I especially like the benefits the DOL-Fin Pilot can offer SCUBA divers.  The low fin resistance induces minimal body pitching, and that allows this monofin to be used by a SCUBA diver wearing a tank on his or her back.  Freedivers have known about the advantages of using a monofin over bi-fins for years, but the technology wasn’t compatible for use with SCUBA.  The DOL-Fin changes that.  The result is more distance covered at greater speeds and with less energy.  Its low effort and high cruising speed capabilities provide a significant advantage for dealing with unexpected currents, even if you are not planning for long range diveing.

The DOL-Fin Orca monofin offers true hyperfin level performance for freediving, but with superior comfort and versatility that will revolutionize what freedivers expect from a monofin.  The swimming characteristics and buoyancy of these fins will not change or degrade with depth, and their durability will outlast other composite blade monofins several times over.  The Orca can also fit in a suitcase, making it less expensive and more practical for traveling with than are other monofins.  Freedivers will love this fin.

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Q: When can I purchase a DOL-Fin?

A: DOL-Fin Orca Mk-2 and X-20 monofins are available now.  The DOL-Fin Pilot is available on a limited bases as part of a beta test program.  You will have to contact us to find out what opportunities are available in the beta test program.

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Q: How is SCUBA diving with a DOL-Fin different from regular diving?

A: For SCUBA divers, the diving style will definitely be different from using bi-fins.  You will be faster in the water and naturally tend to cover more distance.  You likely won't be able to resist the urge to find ways of streamlining your diving kit to expand your newfound capabilities even further.  Eventually, you will find that you are participating in a related, but different sport from where you started.  I like to make the comparison of snow-skiing versus snow-boarding.  They are related, and yet they are two different sports, with their own methods and perspectives.  I think DOL-Fin SCUBA diving will ultimately evolve into a new and different sport as well. 

SCUBA kits will be more optimized for drag reduction, and the overall look and feel of the sport will be less static and become more dynamic.  While many bi-fin divers tend to site dive with a time limit, DOL-Fin divers are more likely to be area divers planning an entry point, route and exit point with a distance limit that is significantly larger than the bi-fin diver for a given air capacity.

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Q: Is it difficult to learn to dive with a DOL-Fin?

A: If you have never used a monofin before, you will definitely find it strange at first to have your feet tied together.  Don't worry, this strangeness will disappear once you find that you can swim much better with a DOL-Fin than you can swim without it.  Learning DOL-Fin swimming is similar to learning to ride a bicycle.  It takes some practice to get the feel for it, but once you learn how, it is easy and feels completely natural.  For some people this happens right away, and for others it can take several hours of practice.  It all depends on the individual's ability for learning new skills.  I have found that young people seem to learn it faster.  Most teenagers have it figured out in 5 to 10 minutes.  I think it is because their brains are more plastic and they simply learn new skills faster than older people who are more set in their ways.

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DOL-Fin Monofin in SuitcaseQ: Does the DOL-Fin fit in a dive gear bag?

A: The DOL-Fin Pilot and X-20 can usually fit into a variety of suitcases and gear bags with just the folding of the fin tips, which is a tool-free process that takes about 10 seconds (example in picture to the right).  For more packing options the fin blade can be removed.  Removing the fin blade requires the removal of 4 screws.

The DOL-Fin Orca also has folding fin tips and the fin blade can be removed by 4 screws similar to the Pilot.  With the fin being separate from the rest of the assembly, the fin blade can be placed diagonally across a suitcase if needed to fit a longer fin in a smaller rectangular space (Example - a 32" fin can fit diagonally in a 30" suitcase). 

A Freediver can typically fit the Orca and all their dive gear in one large suitcase along with the rest of their clothes and only need to check one bag when traveling on the airlines.  With many airlines charging extra for each additional bag, DOL-Fin monofins can save you money on your diving trips every time you travel.  At an average cost of $70 per round trip in the US for a second checked bag, it does not take long for the DOL-Fin products to accumulate significant savings

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Q: How fast is the DOL-Fin?

A: This question does not have a straightforward answer, because there are so many variables that determine someone's swimming speed.  In 2012, when I did my 175 meter national record dynamic record swim with the Orca, my dive time was 125 seconds.  That's an average speed of 1.4 m/s (2.72 knots) including the turns.  In the straight swim, I was probably achieving closer to 3 knots.  This was my speed for maximum economy and going as far as possible on a single breath of air.  Max speeds will be quite a bit faster and, for me, exceed 4 knots. 

When I SCUBA dive with the DOL-Fin Pilot, I typically cruise around at 1.5 to 2.0 knots, but I can sprint at speeds up around 3 mph.  Around 2 knots is where I feel comfortable and maintain my respiratory minute volume low enough for efficient use of my air supply.  I usually dive with a fairly clean and low drag SCUBA kit, but when I go deep I take redundant air supplies which add more drag and my swimming speeds are lower.  The bottom line is that swimming speed depends as heavily on the diver and his or her equipment configuration as it does the swimming fin or fins they are using.

In general, based on propulsive efficiencies, I expect that for a given SCUBA configuration and level of swimming effort, the DOL-Fin will propel a diver 60% to 90% faster than typical dive fins would achieve.

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Q: Which DOL-Fin is right for me?

A:  If you are getting a DOL-Fin for performance freediving, you should be focusing on the DOL-Fin Orca Mk-2.  This monofin was developed specifically to meet the needs of competitive freedivers and recreational freedivers that want hyperfin level performance from a recreational monofin.  The Orca's advantage is in its streamlining to lower the fins drag and boost overall swimming performance.  Performance is fun, so if you can afford it, get the Orca.  Plus the adjustability of the foot binding straps is a nice advantage, especially if you do a variety of warm and cold water diving.

If you are are more focused on cost and comfort and don't need the highest levels of freediving performance, consider the Pilot or X-20.  These fins provide a lot of performance for the money.  They are rugged and have excellent performance and handling qualities for recreational diving and are priced right for most freedivers.  Though not quite a match for hyperfin performance, they will outperform flyer style monofins that currently set the performance bar for recreational freediving.

If you are a scuba diver considering a DOL-Fin, you should be focusing on the DOL-fin Pilot with a 30 inch foil or larger. 

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