Brand: Apollo

Bio-Fin Pro (Stainless Steel Spring Straps)
NSN: 4220-66-152-2592

The Apollo Bio-Fin Pro (Spring Straps) is a professional-grade split-fin propulsion system engineered to maximise underwater propulsion efficiency while significantly reducing diver fatigue. Constructed from 100% natural rubber using Apollo’s proprietary material blend, the fin delivers consistent flexibility, durability and performance across a broad range of operational temperatures.
The hydrodynamic split-blade profile generates forward thrust and lift on both upstroke and downstroke, reducing air consumption by up to 40% compared with conventional paddle fins.
Designed and field-tested for military operations, the Bio-Fin Pro is suitable for surface and subsurface insertions, including helicopter water entry profiles.

Features

• Split-fin propulsion system increases thrust and reduces air consumption by up to 40%.
• 100% natural rubber construction provides flexibility, strength, and consistent?performance across temperature ranges.
• Designed for low drag and reduced leg strain during extended missions.
• Compact hydrodynamic design for helicopter and surface insertion operations.
• Proven in all forms of military diving: MCT, MTO, MCM, and UBDR.
• Non-corrosive components suitable for salt-water and contaminated environments
• The Pro Spring Strap system provides fast, reliable fitting and removal, optimised for streamlined equipment changes in covert and low-profile operational environments.

The World’s No.1 Fin

Voted “BEST OVERALL” (2001-2007)and “TESTER’S CHOICE” (1999-2007) in Rodale / Scuba Lab USA’s annual independent fin review.
The only open heel fin rated EXCELLENT for power vs. stress.
Award winning history.
The only split-fins voted Tester’s Choice 8 years in a row!

Care and Storage Instructions

• After use, wash in fresh water and allow to dry in a well ventilated area out of direct sunlight
• Store in a well ventilated dry area away from direct sunlight

Material: 100% natural rubber
Strap Type: Stainless Steel Spring Straps with Black Heel Protector
Fin Type: Split-Fin
Finish: Matte Tactical Black
Weight: Approx. 1.5 kg per pair
Brand: Apollo

Operational Information

• Operational Compatibility: Compatible with all military and commercial fin retainers, spring strap upgrades available (Bio-Fin Pro Stealth).
• Applications: Maritime Counter-Terrorism (MCT), Maritime Tactical Operations (MTO), Mine Counter-Measures (MCM), and Underwater Battle Damage Repair (UBDR).
• Maintenance: Rinse in fresh water after use; avoid prolonged UV exposure.
• Field Performance: Tested for helicopter drops and diver insertions; maintains propulsion efficiency in both surface and sub-surface operations.

Spring Strap System – OP Benefits

The Spring Strap system is engineered to provide secure retention, rapid deployment and long-term durability in demanding operational environments.
Unlike conventional adjustable rubber straps, the stainless-steel spring core maintains constant tension, automatically compensating for compression changes in wetsuit or drysuit boots at varying depths. This ensures a consistently secure fit without the need for in-water adjustment.
The spring strap configuration reduces handling complexity during equipment changes, allowing rapid fitting and removal while wearing gloves or operating in low-visibility
conditions. Its simplified design eliminates buckles and adjustment points that are prone to wear or failure, improving reliability during extended missions.
The robust construction enhances longevity under repeated operational cycles and harsh marine exposure, while the ergonomic heel pad improves load distribution and comfort during long-duration swims.

How the BIO-FIN Works

The Apollo Bio-Fin delivers enhanced lift and propulsion while requiring reduced diver effort, resulting in greater efficiency and power output per kick cycle.
Unlike traditional flat-blade fins that simply push water vertically, the Bio-Fin generates?forward thrust and hydrodynamic lift on both the upstroke and downstroke. Its engineered blade profile channels water smoothly across the leading and trailing edges, optimising flow dynamics.
The result is controlled lift and accelerated forward movement, operating on principles similar to an aircraft wing to maximise propulsion efficiency.

Fin Stroke Efficiency

The Bio-Fin’s 20º blade angle aligns with the diver’s natural knee and ankle flex, allowing the fin to work with the body rather than against it.
This reduces strain, enhances propulsion efficiency, and improves overall comfort. Apollo’s material selection and engineered blade profile provide fast acceleration and high power output while maintaining low fatigue.

Ergonomic Design

Engineered with a propeller-like action, the Bio-Fin provides superior efficiency over traditional paddle fins.
This design maximises thrust while lowering energy expenditure, enhancing both speed and control. Independent field evaluations confirm that divers can reach and sustain higher speeds with the Bio-Fin than with standard fin designs.

Codification Data

BIO FIN SPRING STRAP KIT

BIO FIN SPRING STRAP SCHEMATIC – 1

BIO FIN SPRING STRAP SCHEMATIC – 2