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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 Classic and HP offer SCUBA divers.  The low fin resistance induces minimal body pitching, and that allows these DOL-Fins 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 stereo-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 than ever before.  Its low effort and high cruising speed capabilities provide a significant safety advantage for dealing with unexpected currents, even though you may not be planning a long range dive.

The DOL-Fin Orca and X-20 monofins offer hyperfin level performance for freediving, but their superior comfort and versatility will revolutionize what freedivers will come to 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.  They are significantly lighter in weight and can also fit in a suitcase, making them much more practical for traveling than are other monofins.  Freedivers will love these fin.

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Q: When can I purchase a DOL-Fin?

A: DOL-Fin Orca, HP, and Classic monofins are available now.  Pre-manufacturing orders for the DOL-Fin X-20 are being accepted through May 21st, 2012.  Deliveries of the X-20 are expected to begin in June 2012.  After May 21st, the X-20 will be transitioned to a regular first-in, first-out ordering to delivery process.

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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. 

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

A: The DOL-Fin X-20 can generally 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.  The X-20 with an XL fin blade will probably require the removal of the fin blade and in this configuration can fit nicely is any generic 36" duffel bag.  Removing the fin blade requires the removal of 4 screws.

The DOL-Fin Orca breaks down with the removal of 4 screws and can fit in a space only 32 inches long.  With the fin being separate from the rest of the assembly, it can be placed diagonally if needed to get more length in a rectangular space.  In this configuration the Orca will fit into many large suitcases for easy travel.  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 the airlines charging extra for each additional bag, the Orca can save you money on your diving trips.

The DOL-Fin HP has the same length fin blade as the X-20 XL.  However, the fin is short enough in length that removing the fin blade is generally not required to fit it in a typical 36" duffel bag.

The DOL-Fin Classic is longer and is unlikely to fit in any typical suitcase.  However, SCUBA divers require more gear than do freedivers and the one bag solution is not really an option anyway.  If you pack all your dive gear and clothes into one big box, it would be over the airline weight limit and you would have to pay for checking two bags anyway.  The solution is a suitcase for clothes and personals, and a separate gear bag for the dive equipment. 

A snowboard gear bag is long enough to fit the DOL-Fin and is generally big enough to carry the rest of your diving equipment as well.  They are sturdy and made with waterproof linings and corrosion resistant zippers.  A snowboard bag makes an excellent DOL-Fin SCUBA gear bag that is inexpensive and readily available.  Furthermore, they are usually on a clearance sale at the start of diving season, as it arrives at the end of the skiing season.

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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.  The products pages show how fast the DOL-Fins are for one solution that represents typical conditions.  This is not the fastest speed possible, but more of an efficient cruise setting and where most people would spend the bulk of their time swimming.  The top speed will be heavily determined by the swimmer's strength and physical fitness; however, most swimmers should achieve at least 1/3 again faster than what is shown on the products performance charts when they exert themselves. 

When I SCUBA dive with the DOL-Fin, I typically cruise around at 1.5 to 2.0 knots.  This 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 freediving, you should be focusing on either the DOL-Fin X-20 or the DOL-Fin Orca.  These monofins were developed specifically to meet the needs of freedivers. 

Between these two models, most customers will want the X-20 because it was designed to deliver the most benefits for the money to freedivers.  It is rugged, has excellent performance and handling qualities and is priced right to be within reach of most freedivers.  The Orca is more of a specialty monofin for customers who want the best performance that money can buy.  It's advantages over the X-20 are the streamlining to lower the fins drag and the adjustability of the foot binding straps.

If you are a scuba diver and are considering a DOL-Fin, you should be focusing on the DOL-fin HP and Classic monofins.  These fins have short lever arms and large fin blades to compensate for the high drag configurations of scuba diving.

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