Neoprene suits and accessories

Choosing the Right Wetsuit Thickness

Neoprene thickness is measured in millimeters and is the primary variable determining thermal protection. The relationship is direct: thicker neoprene traps a larger layer of water against the skin, which the body heats and which then acts as an insulating barrier. The practical ranges are well-established: 2–3 mm suits are appropriate for water temperatures above approximately 24°C and short exposure times; 5 mm suits cover the 18–24°C range comfortably for 45–60 minute dives; 6–7 mm suits extend thermal endurance into the 10–18°C range that characterizes Central European lakes, quarries, and the northern Atlantic coast.

Suit fit is as important as thickness. A wetsuit that fits correctly allows only a thin layer of water to enter and be retained — this water is heated by body temperature within the first minutes of a dive. A suit that is too large flushes this heated layer continuously as the diver moves, replacing it with cold water and negating the insulation value. A suit that is too tight restricts circulation, accelerates fatigue, and makes breathing more difficult when compressing the chest. When in doubt between two sizes, the tighter fit is generally preferable — neoprene relaxes slightly with use and warmth.

Suit Construction: One-Piece vs. Two-Piece, Semi-Dry vs. Wetsuit

Full-length one-piece suits (all the suits listed here) provide better thermal continuity than two-piece systems because there is no water flush point at the mid-body junction. The trade-off is more difficult donning — particularly in the 5–7 mm thickness range where the neoprene is substantially stiffer. The Freddo Extreme series addresses this with an extrastretch neoprene construction that maintains the thermal value of standard 5–7 mm neoprene while requiring significantly less effort to pull on and allowing a greater range of movement during the dive.

The Alaska semi-dry occupies a category between a standard wetsuit and a drysuit. Semi-dry suits use tighter-fitting neoprene seals at the wrist, ankle, and neck — similar in concept to the Donut seal design used on the Gloves 3mm Donut seal and Boots 5mm donut seal — that minimize water entry and prevent the flushing of the heated water layer during movement. In cold European water where a standard 7 mm wetsuit is marginal, a semi-dry suit of the same thickness extends bottom time significantly without the complexity and maintenance demands of a drysuit.

The WHALE skinsuit in the 5 mm category is a different construction: a smooth-skin exterior neoprene suit rather than a fabric-laminated design. Smooth-skin neoprene has lower water absorption and lower water drag, making it popular for snorkeling and freediving. It is more fragile than fabric-laminated neoprene and requires more careful handling against abrasion.

What to Look For

• Water temperature at your dive sites, not air temperature. Divers frequently underestimate the thermal demand of repeated dives over a dive day — the first dive of the day in 18°C water may feel manageable in a 3 mm suit, but by the third dive the core temperature deficit accumulates and the perceived cold becomes significantly more intense. Select suit thickness for the third dive of a cold day, not the first dive of a warm one.
• Suit fit priority: no gaps at wrist, ankle, neck. The three primary water entry points in a wetsuit are the wrist seals, ankle seals, and neck opening. Try the suit fully before purchasing — check that the sleeve ends sit flush against the inner wrist without gaps when the arm is extended forward (as in a fin stroke), that the ankle cuffs don’t gap when the knee is bent, and that the neck seals against the collarbone area without leaving an open channel between the suit and the skin.
• Seam construction and neoprene quality. Entry-level neoprene suits use simple flatlock seaming — the panels are sewn together with the stitching running through the full neoprene thickness, which leaves holes in the seam through which water passes freely. Mid-range and premium suits use blind-stitch (also called glued and blind-stitched) construction where the seam is bonded with neoprene cement and then stitched without the needle penetrating the outer surface, creating a water-resistant seam joint. All Sopras suits in the 5–7 mm range use glued and blind-stitched seam construction.
• Zipper position and type. Back-zip suits are easier to don and doff independently but create a continuous seam at the back of the spine through which cold water can flush. Chest-zip and shoulder-zip designs eliminate this back opening and create a more water-tight seal, but typically require assistance to don. For solo divers, back-zip is more practical; for divers with a consistent buddy, a chest-zip or shoulder-zip is a worthwhile upgrade for thermal performance.
• Accessibility of the Made to Measure option. Standard size ranges cover the majority of body proportions, but divers with non-standard torso-to-leg ratios, very long or short arms, or unusual shoulder widths often cannot achieve a correct fit in off-the-shelf sizes. For these divers, a made-to-measure suit at the price point listed (€280–320) is a practical investment — a suit that fits correctly outperforms a suit three times the price that fits poorly.

Maintenance and Care

FAQ