Deep Apnea Quadraxial 85cm Carbon Fiber Fin Blades

Overview

Deep Apnea Quadraxial 85cm Carbon Fiber Fin Blades are designed for freediving and spearfishing, combining responsive carbon fiber construction with controlled flex for efficient underwater propulsion. Their multilayer structure supports smooth surface swimming, precise movements while hunting, and powerful ascents with reduced kicking effort.

Quadraxial construction and blade response

The Quadraxial structure arranges carbon fibers in four orientations: 0°, +60°, 90°, and -60°. This multidirectional reinforcement helps resist torsional deformation, keeping the blade more stable as it bends and recovers during each kick.

Variable Parabolic Stiffness (VPS) uses the layered carbon construction to control how the blade flexes under load. As the blade bends and returns toward its original shape, it transfers energy into propulsion. This responsive action allows divers to maintain movement with smaller, controlled kicks, particularly useful when approaching fish or adjusting position underwater.

Stiffness selection

Choosing the appropriate stiffness depends on the diver's body weight, leg strength, and kicking technique. The blade should flex sufficiently during each kick to generate propulsion without excessive resistance. A blade that is too stiff can increase leg fatigue, while one that is too flexible may not provide adequate propulsion for the diver.

Foot pocket installation

These are fin blades only; foot pockets must be purchased separately. The blades can be ordered with a mounting-hole pattern prepared for the intended foot pocket or left undrilled for a suitable custom installation. Confirm the foot pocket model before selecting a drilling configuration, as mounting patterns are not universal.

Proper mechanical attachment and compatible foot pockets are important for secure installation and warranty eligibility. Deep Apnea recommends approved foot pocket designs and restricts drilling practices that could compromise the blade structure.

Orders are processed within 2 business days, which includes verification, packing, and dispatch. Orders of $199 or more qualify for free shipping within the contiguous 48 United States. For orders under $199, and for Alaska, Hawaii, or other eligible U.S. destinations outside the lower 48, shipping costs are calculated at checkout based on destination, package weight, and selected service. Certain items may require additional handling or may ship directly from the manufacturer, and we will notify you if extra processing time is expected.

Deliveries are handled by preferred carriers such as USPS, UPS and FedEx and others depending on your location and selected service. Estimated delivery times are displayed at checkout and may vary due to carrier delays, weather, postal disruptions, or other circumstances beyond our control. Once your order ships, you’ll receive a confirmation email with tracking information. Tracking may take up to 24 hours to update on the carrier’s website and is also available through your account when applicable.

We currently ship only to eligible addresses within the United States and do not offer international shipping. P.O. boxes are accepted only when shipping through USPS, and not all packages qualify for this option. If your order does not arrive within the estimated delivery window, please contact us at shop@diveyoung.com so we can assist with locating your package.

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Returns may be requested within 30 days of receiving your order. Items must be new, unused, unworn, and returned with all tags, packing materials, blank warranty cards, manuals, accessories, free items, and original, unaltered packaging. Merchandise that has been used, worn, washed, altered, tested in water, or submerged is not eligible for return. To start a return, please email shop@diveyoung.com for authorization before sending your item back.

Customers are responsible for return shipping costs unless the return is due to an error by Forever Young Outfitters or the item is verified as defective. Defective, missing, damaged, or incorrect items must be reported within 2 business days of delivery, and photos may be required for review. If the issue is verified, a prepaid return label will be provided, and a replacement, store credit, or refund may be issued depending on the circumstances.

After your return is received and inspected, approved refunds are issued to the original payment method and processed within 5–7 business days. Your bank or payment provider may require additional time for the credit to appear. Original shipping and handling charges are nonrefundable, and the value of any included free items that are not returned will be deducted. Returns that do not meet all eligibility requirements may be refused or subject to a 30% restocking fee. We recommend using a trackable and insured service for all customer-arranged returns.

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Many products sold by Forever Young Outfitters include a manufacturer’s warranty covering defects in materials or workmanship. Warranty terms vary by brand, product type, and model, so eligibility, coverage, duration, exclusions, and available remedies are determined by the manufacturer. We recommend reviewing the applicable warranty information before purchase, especially for regulators, BCDs, dive computers, underwater electronics, and other specialized equipment.

If you need warranty service, the claim must follow the process established by the manufacturer, authorized service center, or designated warranty provider. You may be asked for proof of purchase, a serial number, product registration, photos, maintenance records, or other documentation. Forever Young Outfitters does not approve or determine warranty claims, but we are happy to help provide purchase information and direct you to the appropriate manufacturer or service resource.

Keep your receipt, product documentation, serial number information, and original packaging when practical. Damage caused by normal wear, misuse, improper maintenance, corrosion, impact, modifications, or use outside the manufacturer’s specifications may not be covered. Warranty claims are separate from standard returns, so equipment that has been used or submerged may still qualify for manufacturer warranty evaluation even if it is no longer eligible for return.

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