Choosing the right wetsuit for freediving and spearfishing starts with one fundamental decision: selecting the most suitable type of neoprene. While many divers focus on brands and camouflage patterns, the real performance of a wetsuit depends largely on the neoprene construction and the materials used to build it, plus of course the perfect cut and fit.
With the support of Polo Sub, we analyzed the different neoprene sheets used for modern freediving and spearfishing wetsuits. These materials represent the complete neoprene range adopted by the top Italian manufacturer and provide an excellent overview of the solutions currently available on the market.
How Neoprene is Made
Modern neoprene is mainly produced from limestone-based compounds combined with additional materials designed to be as hypoallergenic as possible. During manufacturing, countless microscopic nitrogen-filled cells are created inside the rubber structure. These microcells are responsible for the thermal insulation, buoyancy and elasticity of neoprene.
Apnea Passion Magazine has already explored the production process of neoprene in detail, and the complete article can be found at this link.
The structure and treatment of these nitrogen-filled microcells determine the different neoprene types used in freediving and spearfishing wetsuits.
Open Cell / Lined Neoprene
Open Cell / Lined neoprene is probably the most common solution in the spearfishing world and remains extremely popular also among freedivers.
The internal side of the neoprene consists of the raw open-cell surface. This surface is obtained by slicing a thicker neoprene sheet, exposing the microscopic nitrogen-filled cells. The result is a soft surface that adheres directly to the skin.
The external side is laminated with a textile lining, usually made of nylon, polyester, Lycra or highly elastic proprietary fabrics. This lining significantly improves durability by protecting the neoprene from abrasion against rocks, accidental cuts and tearing during use.
The external fabric also provides protection from sunlight and external environmental agents. During hot summer days it can retain a small amount of moisture that helps reduce overheating when the diver is out of the water. On the other hand, during winter conditions the wet fabric may increase the sensation of cold and requires considerably more time to dry.
The internal open-cell surface creates exceptional adherence to the skin. When the wetsuit fits correctly, the water layer trapped between the body and the neoprene is extremely thin, resulting in excellent thermal insulation. However, this same characteristic makes the wetsuit difficult to put on without lubrication.
For this reason, water mixed with a small amount of soap is normally required. Alternatively, the wetsuit can be worn directly in the sea when water temperatures permit.
An excellent example is shown by Apnea Passion athlete Davide Carrera:
https://www.instagram.com/reel/DZrVCktIK12/?utm_source=ig_web_copy_link&igsh=MzRlODBiNWFlZA==
The main advantages of Open Cell / Lined neoprene are its excellent thermal insulation, high resistance to abrasion, good durability and protection against sunlight. The disadvantages include slightly reduced elasticity compared to pure neoprene solutions, longer drying times and the need for lubrication when putting on the wetsuit.
Open Cell / Smooth Skin Neoprene
Open Cell / Smooth Skin neoprene represents the purest expression of neoprene performance. In this configuration there is no external textile lining, allowing the neoprene to maintain its maximum softness and elasticity.
The internal side remains open cell, while the external smooth skin surface corresponds to the original outer skin of the neoprene sheet before it is cut into thinner layers. This smooth surface is less porous, more compact and more hydrodynamic than open-cell neoprene.
The smooth skin exterior significantly reduces friction in the water, improves hydrodynamics and dries extremely quickly after use.
Because there is no textile lining, Open Cell / Smooth Skin neoprene offers superior flexibility and comfort compared to equivalent lined neoprene. Breathing is easier, body movements are less restricted and the wetsuit adapts perfectly to the diver’s body.
The drawback is its fragility. Smooth Skin neoprene is highly susceptible to cuts, abrasion and accidental tears. Even small damage can rapidly propagate if the material is pulled.
For this reason, extra care is required during transport, dressing and use around rocky environments.
The main strengths of Open Cell / Smooth Skin neoprene are maximum elasticity, exceptional comfort, excellent hydrodynamics, fast drying and outstanding thermal insulation. Its limitations are reduced durability, lower resistance to abrasion and greater sensitivity to UV exposure over time.
Sandwich Neoprene
Sandwich neoprene represents an advanced solution that combines many of the benefits of Open Cell / Smooth Skin neoprene with improved structural durability.
Polo Sub has developed its own proprietary version known as Forza Tre, which is also the name of the wetsuit built using this material.
The construction consists of a 1 mm external Smooth Skin neoprene layer, followed by a highly elastic and water-repellent lining, and finally an internal Open Cell neoprene layer. These three layers are laminated together to create a sophisticated composite structure.
The result is a neoprene that maintains the thermal insulation of Open Cell interiors and the hydrodynamic characteristics of Smooth Skin exteriors, while adding additional structural support through the internal lining layer.
The high-density external 1 mm Smooth Skin layer also improves resistance to compression at depth. Another important advantage is the possibility of sewing through the thin external layer while preserving the integrity of the internal Open Cell section, resulting in stronger seams without compromising thermal insulation.
This technology offers an excellent balance between comfort, insulation, durability and hydrodynamic efficiency. The only disadvantages are the higher production cost, a slight reduction in elasticity due to the internal reinforcement layer and the need for lubrication when putting on the wetsuit.
Lined / Smooth Skin Neoprene
Lined / Smooth Skin neoprene uses an internal lining combined with a Smooth Skin exterior.
The internal lining makes the wetsuit considerably easier to wear because the fabric slides directly over the skin. In many cases, lubrication is unnecessary, making this solution particularly practical.
Externally, the Smooth Skin surface provides excellent hydrodynamics and very rapid drying.
This neoprene construction is frequently chosen for freediving wetsuits in 3 mm and 5 mm thicknesses, but it is also widely used for ultra-thin competition wetsuits in 1 mm and 2 mm thicknesses. These suits are particularly common in dynamic pool apnea and warm-water depth competitions where thermal insulation is required only for short periods.
The internal lining improves durability and allows stitching, which becomes essential when working with very thin neoprene sheets.
Compared to Open Cell interiors, however, the lining reduces direct adhesion to the skin and increases the thickness of the water layer trapped inside the wetsuit, resulting in a partial reduction in thermal efficiency.
Research continues into advanced internal linings capable of matching Open Cell thermal performance, although many of these materials still sacrifice flexibility and comfort.
The greatest strengths of Lined / Smooth Skin neoprene are ease of use, durability, hydrodynamic efficiency and suitability for ultra-thin competition wetsuits. The main compromises involve slightly reduced thermal insulation and a minor reduction in elasticity.
Double Lined Neoprene
Double Lined neoprene features textile lining on both the internal and external surfaces.
This construction is widely used in scuba diving wetsuits and entry-level freediving and spearfishing suits because of its exceptional durability and ease of use.
The double lining makes the wetsuit extremely resistant to abrasion, cuts, nail damage and general wear. Dressing and undressing are straightforward, and the suit can withstand years of intensive use.
The trade-off is reduced flexibility. The two layers of fabric significantly limit the natural elasticity of the neoprene and slightly reduce thermal efficiency. In addition, the fabric layers absorb water and require more time to dry.
For scuba diving this is generally not a major issue because divers typically enter and exit the water only once during a session. For freedivers and spearfishers who repeatedly move between water and surface environments, drying time and reduced flexibility become more noticeable factors.
Despite these limitations, Double Lined neoprene remains an excellent choice for beginners, diving schools and anyone prioritizing durability over maximum performance.
Which Neoprene is Best for Freediving and Spearfishing?
There is no single neoprene that is universally superior. The ideal choice depends on the intended use, water temperature, diving style and personal preferences.
Open Cell / Lined neoprene remains the benchmark for spearfishing thanks to its balance between insulation and durability. Open Cell / Smooth Skin neoprene offers the highest performance for experienced divers seeking maximum comfort and elasticity. Sandwich neoprene represents one of the most advanced solutions currently available, combining insulation, hydrodynamics and structural integrity. Lined / Smooth Skin neoprene excels in competition environments and warm-water diving, while Double Lined neoprene continues to be the most durable and beginner-friendly option.
Understanding these differences allows freedivers and spearfishers to select the wetsuit that best matches their specific needs and diving conditions.
