Maximum Core-Warmth Focus

TB4 Duraskin Air Firewall through the chest and back is designed to shield the core from cold while retaining and recirculating body heat.

Lower-Body Firewall Insulation

TB4 Firewall continues through the thighs, seat, shins and calves, extending thermal coverage across the suit’s major lower-body panels.

Flexible Arms and Shoulders

TechnoButter 4 is used through the arms and shoulders to preserve upper-body mobility despite the suit’s cold-water thickness.

Double-Sealed Stitchless Seams

Exterior Fluid Seam Welds combine with interior recycled TBX tape to create O’Neill’s flexible, watertight double-sealed seam construction.

Integrated Hood

The hooded upper construction provides continuous head and neck coverage for sessions where exposure to cold water, air and wind is a concern.

F.U.Z.E. Chest-Zip Closure

O’Neill’s Front Upper Zip Entry places the opening across the chest for a low-profile closure and an uninterrupted back panel.

360-Degree Barrier

A full barrier surrounds the entry area to manage water entering through the chest opening before it reaches the body of the suit.

Drainholes

Integrated drainholes allow water caught within the entry barrier to escape instead of remaining around the upper torso.

Anti-Flush Barrier

The F.U.Z.E. entry incorporates an anti-flush barrier to reduce sudden water movement through the chest and neck area.

Redzone Water-Resistant Zipper

The Redzone chest zipper adds another level of water resistance to the upper-entry system.

TB4 Duraskin Air Firewall

Used through the chest and back, TB4 Duraskin Air Firewall provides the Psycho Tech’s primary core-insulation system and helps retain body heat.

TB4 Firewall

The thighs, seat, shins and calves use TB4 Firewall to extend thermal performance throughout the lower body.

TechnoButter 4

The arms and shoulders use TechnoButter 4 to balance the suit’s substantial warmth with the flexibility required for paddling and active movement.

TechnoButter 4X Entry

O’Neill’s most stretch-focused listed material is placed through the entry to help the chest opening flex during entry and exit.

Stitchless Exterior

The Psycho Tech uses stitchless exterior Fluid Seam Weld technology rather than exposed exterior stitching.

Fluid Seam Weld Technology

Flexible exterior seam welds reinforce the panel connections and form the outer layer of the suit’s watertight seam system.

Interior Recycled TBX Tape

Recycled TBX tape seals the seams from the inside, creating a second layer of reinforcement and water control.

Double-Sealed Construction

The exterior welds and interior tape work together to provide O’Neill’s water-tight, double-sealed seam construction.

Recycled Oyster Shells

Recycled oyster-shell material is incorporated into the neoprene formulation as part of O’Neill’s updated material package.

Eco Carbon Black

Eco Carbon Black is infused into the neoprene construction alongside the recycled oyster-shell content.

Recycled Dope-Dyed Jersey

The Psycho Tech uses recycled dope-dyed yarn jersey in its laminated fabric construction.

Aqua Alpha Lamination

O’Neill uses Aqua Alpha solvent-free neoprene lamination to bond the suit’s materials.

Super Seal Cuffs

O’Neill’s Super Seal Cuffs create a close connection at the wrists and ankles to help control water movement through the extremities.

Plasma Wrist Seals

Plasma seals reinforce the wrist openings and help maintain a secure fit during active sessions.

Plasma Ankle Seals

Matching Plasma seals at the ankles support a close lower-leg opening and complement the Super Seal cuff construction.

Key Pocket with Loop

A built-in key pocket and retention loop provide secure storage for a compatible non-electronic key.

Choose the Psycho Tech

Choose the Psycho Tech when maximum cold-water warmth, a fixed hood, TB4 Firewall insulation and double-sealed stitchless seams are the priorities.

Choose the Mutant II

Choose the Mutant II when you want a modular system that can switch between hooded and non-hooded neck closures as conditions change.

Best Rider Profiles

• Surfers prioritizing maximum cold-water warmth
• Riders who want a permanently hooded full suit
• Anyone seeking premium stitchless seam construction
• Surfers who need strong anti-flush protection
• Riders who want thermal lining across the core and legs
• Cold-water riders who still value shoulder flexibility
• Anyone seeking O’Neill’s premium Psycho Tech construction

What You’ll Notice in the Water

• Substantial core and lower-body insulation
• Flexible movement through the arms and shoulders
• Full head and neck coverage
• A low-profile chest-entry system
• Reduced flushing through the upper entry
• Secure wrist and ankle seals
• Double-sealed panel connections
• Stretch through the TechnoButter 4X entry

Standard Sizes

S, M, L, XL and XXL use O’Neill’s standard height and body-measurement proportions.

Short Sizes

MS, LS and XLS provide the chest and waist room of their base size with shorter height proportions.

Tall Sizes

MT, LT and XLT provide longer height proportions for riders who need additional torso, arm and leg length.

Need Help Choosing?

Call Windance with your height, weight, chest and waist measurements. We can help narrow down the best O’Neill size before you order.

Wetsuit Configuration

• O'Neill Psycho Tech 5/4mm+ full wetsuit
• Windance thickness designation: 5.5/4mm
• Integrated hood
• F.U.Z.E. chest-zip entry
• Full-length arms and legs

Additional Details

• Color: Black/Black
• Men’s wetsuit sizing
• Key pocket with retention loop
• Sizes S through XXL
• Short and tall size options

Is this a 5/4mm or 5.5/4mm wetsuit?

O’Neill officially calls it a 5/4mm+ suit and states that PLUS construction adds 0.5 mm. The product URL and Windance title identify this configuration as 5.5/4mm.

Is the hood removable?

No modular hood system is listed for the Psycho Tech. This model is sold as a hooded full wetsuit with the hood integrated into its cold-water configuration.

What is TB4 Duraskin Air Firewall?

It is the thermal material used through the chest and back to shield against cold while retaining and recirculating body heat.

Where is TB4 Firewall used?

TB4 Firewall is used through the thighs, seat, shins and calves.

Where is TechnoButter 4 used?

TechnoButter 4 is used through the arms and shoulders, while TechnoButter 4X is used through the entry.

What does F.U.Z.E. mean?

F.U.Z.E. is O’Neill’s front upper zip entry system. On this suit it includes a Redzone water-resistant zipper, 360-degree barrier, drainholes and an anti-flush barrier.

How are the seams sealed?

The exterior uses stitchless Fluid Seam Weld technology, while the interior is reinforced and sealed with recycled TBX tape.

Does it have sealed wrists and ankles?

Yes. The suit uses Super Seal Cuffs with Plasma wrist and ankle seals.

Does it use recycled materials?

Yes. O’Neill lists recycled oyster shells, Eco Carbon Black, recycled dope-dyed yarn jersey and recycled interior TBX seam tape.

Does it use solvent-free lamination?

Yes. O’Neill specifies Aqua Alpha solvent-free neoprene lamination.

What water temperature is it designed for?

O’Neill does not provide one fixed temperature range in the written product specifications. Suit choice depends on water and air temperature, wind, session length, activity level and personal cold tolerance.

Does it have key storage?

Yes. The suit includes a key pocket with a retention loop for a compatible non-electronic key.