The next generation in our record-breaking monofin line.
The PRO Monofin 4 Fiberglass is the next generation in our line of record-breaking monofins. With a new captivating design, optimized stiffness inserts that give you more “spring” in your kick and better energy transition, and your choice of customizations, you’ve never been more ready to explore new depths.
Tailor your monofin specifically to your build, strength, and diving technique with the PRO Monofin 4 Fiberglass - the most customizable fiberglass monofin in our range of monofins. Customization options include blade and accent color, blade size, blade stiffness, and the choice between standard-sized or customized foot pocket size, fit, and angle.
The PRO Monofin 4 Fiberglass features a durable fiberglass blade that is in the top-performance range for both fiberglass and carbon blades overall. The captivating new blade design features double-lined blade accents, now on both ends of the blade, with a smoothed-out silhouette. Additionally, optimized inserts are now placed into foot pockets according to blade stiffness, giving them a more ‘spring-like’ effect for better transition of energy from the feet to the blade.
The soft and medium stiffness options of the PRO Monofin 4 Fiberglass are ideal for freedivers who use an ankle-driven technique that focuses on both a strong front and back kick. The blade-layering structure has been updated to support this low-effort, almost straight leg technique by keeping the load on the ankles. The standard foot pocket angle is set at 30° but can be customized depending on the flexibility of your ankles.
For a full guide on each customization option and to understand what is right for you, see the ‘Size and Customization Guide’ section below.
Details and Materials
Materials: 100% UHC fiberglass
Handcrafted from start to finish
Hand-layered blades for superb response and feel
Choose between a Small and Regular blade size according to your build
Molchanovs Hand-Built Foot Pockets:
Heavy-duty, wear-resistant, and UV-resistant
Custom open-heel foot pockets for flexibility
Comfort Lining interior with soft micropore for maximized comfort
Increased toe space for added relief
Engraved Molchanovs logo on the front
Choose between standard EU sizes or custom sizes with supinator support and choice of fit
Foot pocket Angle: 30° standard angle
Can be customized to 25° and 35°
Overall Length (depending on foot pocket size):
Small Blade: 70-72cm (27.6 - 28.3in)
Regular Blade: 72-74cm (28.3 - 29.1in)
Small Blade: 68cm (26.8in)
Regular Blade: 70cm (27.6in)
Weight: 2.6kg (5.7lb)
All equipment should be rinsed in fresh water after use and placed out of direct sunlight and heat. Do not place heavy objects on top of the fins. For more information, see how to care for your freediving bifins and monofin here. Additionally, see how to travel with your bifins and monofin here.
A 1-year limited warranty applies. Please note that defects or damage to the equipment caused by improper or incorrect use or insufficient/improper maintenance and product care will render our Warranty Policy null and void.
Standard Molchanovs Hand-Built Foot Pocket Sizing
Please note: If you have a noticeable size difference between each foot, wider feet, or especially high or low arches, we suggest ordering custom foot pockets. Follow the ‘Custom Hand-Built Foot Pocket Sizing’ guide below to measure your feet correctly.
Custom Hand-Built Foot Pocket Measurement Guide
Custom Foot Pocket Fit Guide The desired fit determines the tightness of the foot pockets. Three options are available:
Comfortable: Allows more space inside of the foot pockets for the feet. The feet will feel like they are on the verge of movement, but will not actually have movement since any friction between the feet and foot pockets will cause blisters. Comfortable for about 2 hours of wear.
Normal:More comfortable compared to the Tight fit. There is slightly more space inside for the feet, but not enough space for extra movement. Allows for about 20 - 50 minutes of wear.
Tight:Specifically designed for performance, which means that the fit is especially tight. This gives you the best control over the blade as the feet are very compressed with no space for any extra movement inside of the foot pocket. Suitable for about 10 - 30 minutes of wear.
Please note: The maximum time a freediver can wear foot pockets (especially Tight fit) depends on their level of experience and how flexible their feet are. If you would like to improve your foot flexibility, watch this video.
Choosing Monofin Blade Stiffness Blade stiffness depends on your height, weight, technique, experience, training goals, and blade size. Below are general tips on how to choose the right stiffness. If you are not sure, e-mail firstname.lastname@example.org with a video attached of one of your dives for a recommendation.
Soft: Suitable for smaller and lighter freedivers, and also for experienced freedivers with excellent ankle-driven technique. Softer blades are more economic in terms of energy consumption, although it mostly remains a preference among freedivers with more strength whether to choose a soft or medium stiffness.
Medium: Suitable for larger and heavier freedivers, freedivers with more lower-body strength, or for freedivers who needs more power.
Choosing Monofin Blade Size We also offer the choice of a Small monofin blade for freedivers who are under 65kg (143lb), shorter than 170cm (5 feet 6 inches), or with shorter leg proportions. Small blades are 2cm (0.8in) shorter than Regular blades in length and width, and are particularly ideal for shorter freedivers because of their ease of maneuverability while additionally requiring less power and energy spent on kicks. While the blade-layering structure of both Small and Regular blades are the same, the reduced surface area of the Small blade can make them feel softer than Regular blades.
If you are on the smaller and lighter side (or if you prefer a more agile monofin), choose a Small blade. If you are on the taller or heavier side (or if you prefer a more powerful monofin), choose a Regular blade.
Choosing Foot Pocket Angle The standard 30° foot pocket angle will emphasize the back kick. If you have very flexible ankles, we recommend you choose a 25° foot pocket angle to balance the load between the ankles and hips. For stiffer, less flexible ankles, choose a 35° angle.
Production time for customized monofins take approximately 5 - 6 weeks depending on the volume of orders. Standard monofin orders may be ready to be shipped as soon as you order depending on availability.
Shipping and Returns
See the Shipping and Returns section of the FAQ here.