UltimateSwimFin.com - Home of the Lunocet Monofin worn by Michael Phelps

"The most fun you can have with your swimsuit on!" The Lunocet provided Michael Phelps with 349% more propulsion, allowing him to swim 87% faster than his 2009 World Record!


Frequently Asked Questions:

Q: What type of cycling shoes fit / work well with the Lunocet?

A: 3-bolt road cycling or triathlon cycling shoes work with the Lunocet.  Shimano and Sidi are 2 brands that fit, work particularly well with water (the epoxies hold up well) and are readily available.  Either leather or synthetic material will work well for the shoe tops.  Expensive carbon soles are not required / necessary for good performance with the Lunocet.  Velcro fasteners tend to be the simplest and most reliable.


Q. Do I need "clips" or "cleats" for my cycling shoes to attach to the Lunocet?

A. No - the Lunocet bolts directly to the holes in the soles of the cycling shoes with the bolts and allen wrench supplied


Q. How does the 30-day money back guarantee work?

A. If for ANY reason, you are unsatisfied with the Lunocet, please email us and return it for a full refund, no questions asked.  We are so confident in the Lunocet that we can offer this guarantee and have never had one returned.  


Q. How does the 3-yr warranty work?

A. If you have any problems mechanically with your Lunocet, please email us directly and we will either send you a replacement part directly or have you send in your Lunocet for repair at our facility, depending on the nature of the issue.  


Q. What sort of "break-in" period is recommended with the Lunocet 

A. Use the Lunocet the way it was shipped to you and expect anywhere from 4-8 hrs of usage to allow the Lunocet to "break-in" properly.  Some additional flexibility will occur and the parts will "find their happy place" and allow for smooth operation and proper flex / "peduncle articulation".


Q. How do I adjust the stiffness and what setting should I use?

A. After the break-in period, if you feel that you want more propulsion and acceleration add a second pin (provided) to the hole next to the one already in place.  You may have to use a punch and a hammer to tap the pin securely in place.  Once you have used this setting for a while and if you still require more stiffness, a 3rd pin can be added in the same manner.  Pins may also be removed the same way.


Q. What are some guidelines / recommended settings?

A. For smaller people, those with less strength and very smooth freedivers may be fine with a single pin.  Larger freedivers, stronger people and those looking to put more energy into their kick & average sized people wanting to sprint, may find 2-pins optimal.  Heavy swimmers and larger people wanting to sprint and put maximal effort into each kick may want to put all 3 pins in place.


Q. What happens if I use too stiff of a setting for my strength / application?

A. If you overly-stiffen the spring for your intended usage, the jointed vertebrae in the Lunocet will not flex and you will find that the fin creates too much "drag" and it will be inefficient and too energy intensive.


Q. What does the name "Lunocet" mean?

A.  "Luno" is for the shape of the tail which falls under the categorization of a "lunate propulsor" which speaks to its moon-shape, and "cet" is an abbreviation for the infra-order of 90 species of whales, dolphins and porpoises, called Cetaceans. 


Q. What sorts of people should use a Lunocet monofin and what considerations should I take into account?

A. Our customers span a wide variety of ages and types of people.  If you are in good health and have the proper aquatic background and / or training, there is no reason why you can not use the Lunocet into your 80's and beyond!  We have one very prominent customer who does just this multiple times per week!!  Please see our Safety Considerations page for more info.