THE DEEP SPEARFISHING STORY
Deep Spearfishing is a specialized carbon fin designed for deep vertical spearfishing, demanding ascents and diving in currents.
The blade is engineered to provide strong and efficient propulsion when power is especially important during the ascent from depth.
Its progressive carbon structure is designed to combine powerful thrust with controlled flex, helping the diver maintain efficient movement throughout the dive.
This model is primarily intended for deep spearfishing rather than general-purpose shallow-water hunting.
WHY DEEP SPEARFISHING?
DEEP POWER
Designed to deliver strong propulsion during deep vertical dives and demanding ascents, where efficient power transfer is essential.
STABILITY
The blade structure and water rails are designed to provide controlled flex, stability and predictable handling during powerful fin strokes.
LONG-TERM PERFORMANCE
Built for intensive use with high-quality materials and controlled manufacturing processes. BlackTech carbon fins are designed for long-term performance.
HARDNESS GUIDE
Choose the hardness according to your body weight and preferred fin stiffness.
Soft — 70–85 kg
Medium — 85–95 kg
Hard — 95+ kg
Hardness selection: Our hardness recommendations are based on the diver’s body weight, assuming approximately 4–6 kg of lead is used for dives beyond 15–20 m. Individual preferences, diving technique and physical strength may also influence the ideal hardness.
If you are between two options or are unsure which hardness is right for you, contact us for a recommendation.
FOOT POCKET OPTIONS
Mares Razor
Omer Stingray
Pathos
Custom foot pocket options are also available on request, including C4, Cressi, Seac, Spetton and Picasso.
TECHNICAL SPECIFICATIONS
Mares Razor
Overall length: 812 mm
Omer Stingray
Overall length: 814 mm
Pathos
Overall length: 790 mm
Bending length: 667 mm
Blade width: 190 mm
Blade angle: 22°
CONSTRUCTION & TECHNOLOGY
100% high-tensile carbon fiber combined with a specially formulated epoxy system.
The blade features a variable structure, with controlled stiffness distribution designed to provide powerful propulsion while maintaining progressive flex.
BlackTech uses laser-controlled carbon layer positioning to achieve consistent blade characteristics and precise stiffness distribution.
The blades are manufactured using VRTM technology with high temperature and high vacuum processing to achieve a highly consistent laminate with 0% void level.
The manufacturing environment is controlled for temperature and humidity. Each carbon blade undergoes two 14-hour post-curing cycles controlled by PLC technology with temperature deviation of less than ±0.1°C.
The result is a precisely manufactured carbon blade designed for powerful, controlled and efficient propulsion during deep diving.
WATER RAILS & FINISH
Deep Spearfishing features blue water rails designed to improve water flow during blade flexing, helping to reduce turbulence and improve stability and handling.
The blades feature BlackTech's signature mirror finish on the front and back surfaces.
WHO IS DEEP SPEARFISHING FOR?
Deep Spearfishing is designed for experienced spearfishers who primarily focus on deep vertical diving.
It is particularly suited to:
• Deep spearfishing beyond 30 metres
• Powerful and demanding ascents
• Diving in currents
• Divers who prioritize strong vertical propulsion
• Spearfishers looking for a specialized deep-diving carbon fin
For shallow-water hunting, long surface swimming or general-purpose use, consider our Normal Spearfishing & Freediving or CST Competition models.
WARRANTY
Deep Spearfishing carbon fins come with a 3-year written warranty.
The warranty applies according to BlackTech's official warranty terms.
PRODUCTION & DELIVERY
BlackTech fins are produced upon order.
Typical production time is 25–45 business days, depending on current production workload.
Made in EU.
FAQ
Who are Deep Spearfishing fins designed for?
They are designed primarily for spearfishers who focus on deep vertical diving, demanding ascents and diving in currents.
Which hardness should I choose?
Soft is designed for divers weighing 70–85 kg, Medium for 85–95 kg and Hard for 95+ kg. If you are between two options or are unsure, contact us for a recommendation.
Can I use Deep Spearfishing fins in shallow water?
They can be used in shallow water, but the model is specifically developed for deep vertical spearfishing. For a more versatile all-round fin, consider Normal Spearfishing & Freediving or CST Competition.
Which foot pockets are available?
Deep Spearfishing is available with Mares Razor, Omer Stingray and Pathos foot pockets. Other foot pockets can be prepared on request.
How deep can I dive with Deep Spearfishing fins?
The model is designed for deep vertical spearfishing, including dives beyond 30 metres. Actual diving depth should always depend on the individual diver's training, experience and safety procedures.
How long does production take?
Typical production time is 25–45 business days, depending on current workload.
Is Deep Spearfishing covered by a warranty?
Yes. The carbon fins come with a 3-year written warranty according to BlackTech's warranty terms.





