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O'NeillPsycho One 4/3mm Back-Zip Full Wetsuit - Men's

O'NeillPsycho One 4/3mm Back-Zip Full Wetsuit - Men's

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5 out of 5 stars
2 Reviews

Psycho One 4/3mm Back-Zip Full Wetsuit

For unrestricted mobility, buttery-soft neoprene comfort, and an incredible fit while you surf, turn to the O'Neill Men's Psycho 1 Z.E.N. 4/3 Wetsuit. The Psycho 1's ultra-gooey 4/3mm Technobutter neoprene holds more air bubbles so that it absorbs less water to give you a lighter, warmer, and more flexible feel. Ideal for cold to cool surfing conditions, its fluid seam welded construction uses a silicone-based urethane seal applied to the opposite side of its glued and blind-stitched seams to block out water without restricting flexibility. Plasma wrist and ankle seals also prevent flushing.

The Psycho 1's strategic seamless paddle zones and seamless shoulder design further enhance flexibility. O'Neill engineers gave the Psycho 1 a Z.E.N. back entry system with drain hole which features a pullover internal neck seal that blocks out water for maximum performance. Any water that does happen to penetrate the Z.E.N. collar or super-short zip is blocked by the Barrier-2 and forced out the drain hole. A double super seal neck also provides wide adjustability and a comfortable closure. Plus, an external key pocket with loop ensures that you're not locked out of your car or hotel at the end of the day.


  • Wetsuit for cool to cold ocean and river surfing
  • 4/3mm TechnoButter neoprene stays warm down to upper 50s
  • Z.E.N. zip closure includes rash-reducing neck liner
  • TechnoButter retains 30% less H2O than other neoprene
  • Minimal welded seams reduce chafing and boost durability
  • External key pocket wi/ loop reduces parking stress
  • Seamless shoulder make for comfortable all-day paddling
  • Item #ONE015M

Tech Specs

TechnoButter 2 neoprene
full suit
Water Temp
Z.E.N. back zip
Seam Construction
super seam weld
Manufacturer Warranty
1 year

Overall Rating

5 based on 2 ratings

Review Summary

5 Stars - 2 reviews
4 Stars - 0 reviews
3 Stars - 0 reviews
2 Stars - 0 reviews
1 Stars - 0 reviews

Fits True To Size

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