These Fourth Element Tech fins are open-heel diving fins designed for control, durability, and reliable propulsion in harsh conditions. The Military Spec variant of the Fourth Element tech fins is aimed at technical, public safety, and military divers who need simple, robust scuba fins that work with boots and heavy gear.
Use these Fourth Element fins when you want stable trim, efficient frog kicks, and predictable handling in current or confined spaces.
- What it is: Open-heel technical fin with stiff blade for precision kicks.
- Best for / not for: Best for drysuit, cold water, and ocean training; not for lightweight travel or barefoot use.
- Key compatibility: Works with neoprene or drysuit boots; check size with your boot thickness.
Instant Power, Predictable Control
A firm, vented blade translates leg input directly into thrust for rock-solid stability during frog, back, and helicopter kicks. The consistent response reduces effort when holding position in current or tight spaces.
- Vents reduce drag on the recovery stroke
- Rigid rails keep the blade tracking straight
- Balanced stiffness for technical finning styles
Military-Spec Ruggedness
Built for hard use, the Tech Fin (Military Spec) pairs dense rubber with reinforced strap posts and natural rubber & bungee strap. The low-glare finish resists scuffs while remaining easy to rinse and maintain between dives.
- Heavy-duty posts resist lever stress
- Bungee strap holds tension in all temperatures
- Wide heel pad for quick donning with gloves
Trim-Balanced Buoyancy
A negative-to-balanced buoyancy profile helps counter floaty feet from thick wetsuit or drysuit boots, supporting a flat, efficient body position that reduces drag and gas consumption.
- Predictable in both fresh and salt water
- Encourages horizontal posture
- Confident contact in silt-out conditions
Low-Maintenance, Travel-Ready
The compact, stackable shape packs easily, while dense rubber shrugs off boat decks, ladders, and shore entries. Rinse, stow, and go—no special care required.
- Resistant to UV, abrasion, and ozone
- Foot pocket shaped for sturdy boots
- Simple hardware—no plastic ratchets to break
Pros & Cons
Pros
- Precise control for frog/back kicks
- Durable construction for heavy use
- Glove-friendly strap handling
- Boot-compatible open-heel pocket
Cons
- Heavier than travel-oriented fins
- Not intended for barefoot use
- May require size up for rock boots
Why Buy from Bluewater Photo
- Authorized Fourth Element dealer—genuine products with manufacturer warranty
- Diver-tested gear recommendations and real-world setup advice
- Responsive support from our expert team by phone, chat, or email
- Fast shipping and careful packaging
Power through the water, hold your position, and focus on the dive—not your fins.
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Learn More — Guides & Articles
- Best Scuba Fins for 2024 — Our top picks for the best scuba fins for 2024.
- Scuba Essentials for better underwater photographs — Our suggested scuba gear for taking photos underwater
- Underwater Photography Guide — lighting & strobe technique fundamentals
- Best Regulator Guide 2024 — ensure you have the perfect regulator for underwater photography
Specifications
- Build
- Material: dense natural-rubber blade and foot pocket
- Finish: low-gloss/matte, easy-rinse surface
- Hardware: stainless steel spring straps with wide heel pad
- Hydrodynamics
- Vented blade reduces recovery resistance
- Rigid rails support powerful, controlled thrust
- Optimized for frog, back, and helicopter kicks
- Buoyancy & Trim
- Negative-to-balanced buoyancy profile (size-dependent)
- Helps counter floaty feet with thick boots/drysuits
- Stable feel in fresh and salt water
- Foot Pocket & Fit
- Open-heel design for wetsuit and drysuit boots
- Rounded edges to protect suit fabric
- Sizes: S–XL (see size chart for guidance)
- What’s Included
- Pair of Fourth Element Tech Fin (Military Spec)
- Pre-installed stainless steel spring straps
- Compatibility
- Works with standard neoprene and drysuit boots
- Fits most bolt-snap leash attachment methods
- Suitable for recreational, technical, and professional use
Size Guide:
- Medium: UK 4-7 / US 5-8 / EUR 36-41
- Large: UK 8-10 / US 9-11 / EUR 42-44
- X Large: UK 10-12 / US 11-13 / EUR 44-46
- XX Large: UK 12-14 / US 13-15 / EUR 46-48
Fourth Element Tech Fin (Military Spec) — FAQ
- What are the Tech Fins made of?
They use natural rubber with a tuned density gradient and a vented blade to balance comfort and stiffness. This design reduces drag and improves thrust on frog and back kicks.
- Are the Military Spec Tech Fins negatively buoyant?
Yes—Tech Fins are slightly negative in the water, which helps keep feet down in drysuits and technical rigs.
- Do these fins come with bungee or spring straps?
The Military Spec listing at Bluewater Photo notes a bungee heel strap with reinforced posts and a low-glare finish. If a different strap is required, please verify availability before purchase.
- Which boot types and sizes fit these fins?
They’re open-heel fins for neoprene and drysuit boots. Reference sizing (men’s): M US 5–8, L US 9–11, XL US 11–13, XXL US 13–15; fit can vary with boot bulk—rock boots may need a size up. Please verify this specification with Bluewater Photo before purchase.
- How do these compare to classic Jet-style fins for travel and trim?
They use a shorter, wider blade for maneuverability while maintaining thrust; weight is comparable or slightly lighter than some Jet-style fins in similar sizes. This can aid trim without adding excess length in tight spaces.
- Are these fins suitable for drysuit and cold-water diving?
Yes. The open-heel pocket and slightly negative buoyancy work well with drysuit boots for controlled trim in colder water.
- What’s the recommended maintenance?
Rinse with fresh water after each dive, avoid prolonged heat/UV, and store flat. Inspect bungee/strap posts regularly and replace worn parts as needed.
- What about warranty, returns, and Bluewater Photo support?
Bluewater offers expert, lifetime advice and free shipping on orders over $200 in the U.S. and Canada. Manufacturer warranty and return window can vary—please verify this specification with Bluewater Photo before purchase.
Why Buy from Bluewater
1. Proof of Expertise
- Authorized Garmin dealer — full manufacturer warranty.
- Founded and staffed by active divers, underwater photographers, and explorers.
- Decades of combined hands-on experience with the gear we sell.
- We test and use most of the equipment ourselves before recommending it.
2. Risk-Free Purchase (See Terms Of Service)
- 30-day, hassle-free returns (unused condition).
- Secure payment with trusted gateways (credit card, PayPal, etc.).
- All products shipped in factory-sealed boxes (unless stated).
- Transparent policies — no hidden fees or fine-print surprises.
3. Fast & Reliable Delivery
- Free U.S. shipping over $200 for Photo Gear & $50 for Dive Gear.
- Same-day dispatch on in-stock orders placed before 12pm.
- Worldwide shipping options with reliable carriers.
- Real-time tracking updates sent straight to your inbox.
4. Extra Value at No Extra Cost
- Lifetime product support by email, phone, or in-store.
- Setup help & usage tips tailored to your needs.
- Exclusive buyer’s guides, tutorials, and dive trip invitations.
- Early access to special promotions & new releases.
5. Social Proof & Community
- Thousands of satisfied divers & underwater photographers worldwide.
- 5-star average product & service ratings.
- Active in dive events, conservation projects, and photography competitions.
6. Personal Connection
- Direct line to our in-house experts — no outsourced call centers.
- Friendly, passionate staff who speak “diver” fluently.
- We care about your whole adventure, not just the sale.
We offer lifetime support with all purchases.
Please call or email us with any questions; our knowledgeable staff would love to assist you.
Size Guide:
- Medium: UK 4-7 / US 5-8 / EUR 36-41
- Large: UK 8-10 / US 9-11 / EUR 42-44
- X Large: UK 10-12 / US 11-13 / EUR 44-46
- XX Large: UK 12-14 / US 13-15 / EUR 46-48
Fourth Element Tech Fin (Military Spec) — FAQ
- What are the Tech Fins made of?
They use natural rubber with a tuned density gradient and a vented blade to balance comfort and stiffness. This design reduces drag and improves thrust on frog and back kicks.
- Are the Military Spec Tech Fins negatively buoyant?
Yes—Tech Fins are slightly negative in the water, which helps keep feet down in drysuits and technical rigs.
- Do these fins come with bungee or spring straps?
The Military Spec listing at Bluewater Photo notes a bungee heel strap with reinforced posts and a low-glare finish. If a different strap is required, please verify availability before purchase.
- Which boot types and sizes fit these fins?
They’re open-heel fins for neoprene and drysuit boots. Reference sizing (men’s): M US 5–8, L US 9–11, XL US 11–13, XXL US 13–15; fit can vary with boot bulk—rock boots may need a size up. Please verify this specification with Bluewater Photo before purchase.
- How do these compare to classic Jet-style fins for travel and trim?
They use a shorter, wider blade for maneuverability while maintaining thrust; weight is comparable or slightly lighter than some Jet-style fins in similar sizes. This can aid trim without adding excess length in tight spaces.
- Are these fins suitable for drysuit and cold-water diving?
Yes. The open-heel pocket and slightly negative buoyancy work well with drysuit boots for controlled trim in colder water.
- What’s the recommended maintenance?
Rinse with fresh water after each dive, avoid prolonged heat/UV, and store flat. Inspect bungee/strap posts regularly and replace worn parts as needed.
- What about warranty, returns, and Bluewater Photo support?
Bluewater offers expert, lifetime advice and free shipping on orders over $200 in the U.S. and Canada. Manufacturer warranty and return window can vary—please verify this specification with Bluewater Photo before purchase.
Why Buy from Bluewater
1. Proof of Expertise
- Authorized Garmin dealer — full manufacturer warranty.
- Founded and staffed by active divers, underwater photographers, and explorers.
- Decades of combined hands-on experience with the gear we sell.
- We test and use most of the equipment ourselves before recommending it.
2. Risk-Free Purchase (See Terms Of Service)
- 30-day, hassle-free returns (unused condition).
- Secure payment with trusted gateways (credit card, PayPal, etc.).
- All products shipped in factory-sealed boxes (unless stated).
- Transparent policies — no hidden fees or fine-print surprises.
3. Fast & Reliable Delivery
- Free U.S. shipping over $200 for Photo Gear & $50 for Dive Gear.
- Same-day dispatch on in-stock orders placed before 12pm.
- Worldwide shipping options with reliable carriers.
- Real-time tracking updates sent straight to your inbox.
4. Extra Value at No Extra Cost
- Lifetime product support by email, phone, or in-store.
- Setup help & usage tips tailored to your needs.
- Exclusive buyer’s guides, tutorials, and dive trip invitations.
- Early access to special promotions & new releases.
5. Social Proof & Community
- Thousands of satisfied divers & underwater photographers worldwide.
- 5-star average product & service ratings.
- Active in dive events, conservation projects, and photography competitions.
6. Personal Connection
- Direct line to our in-house experts — no outsourced call centers.
- Friendly, passionate staff who speak “diver” fluently.
- We care about your whole adventure, not just the sale.
We offer lifetime support with all purchases.
Please call or email us with any questions; our knowledgeable staff would love to assist you.
