In this article, I talk about the second wetsuit I received from C4 Carbon Freediving, the Sideral, a 5mm two-piece model characterized by the Silver color and carbon-effect print.

The Sideral was designed with a minimum number of panels to reduce seams, thus increasing comfort and elasticity. The inner lining is highly elastic, and the wetsuit is glued on the outside and stitched on the inside. It is designed for freediving, and the cut is identical to that of fishing wetsuits. It is made with glide skin neoprene on the outside and highly elastic jersey lining on the inside. The neoprene is certified to be free from any harmful chemicals, such as phthalates and latex, that could damage the environment or human health.

When I received it, I decided to wait a few months before testing it in the sea, in January. I live in Porto Sant’Elpidio, a small town where the beach stretches for many kilometers. Finding depth around here is challenging, and I usually go on a friend's fishing boat, navigating for 14 miles to reach depths of 38/40 meters. At the end of January, I will go for a dive with Emiliano Lagatti from Apnea Smart to test my brand new Sideral by C4.

In winter, or at the start of the season, I prefer to start with the pants already on at home, while I put on the jacket directly on the beach or at the port. As with the other model I tried earlier, I notice that there are no cotton gloves for dressing, which are essential, especially for us women, with smooth wetsuits.

I really appreciate the fit of C4 wetsuits, and the Sideral is no exception. The pants can be worn dry or even in the water, depending on how much you feel the cold. It's always very easy to put them on dry; the inner lining is super elastic, and they slide on quickly. The ends around the ankles have reinforced edges to seal and prevent water from entering. The fit is perfect, and the waist is not too high. I love the design and print. The Sideral in this test is silver, but you can also get it in gold. The back of the pants is completely black, while the front, up to just above the knee, has a full section that can be silver or gold, giving a "Parisian" effect. Once on the beach, it’s time for the jacket. The glide skin neoprene and the highly elastic inner jersey lining make this phase very easy. I start with the arms, which have reinforced edges at the wrists. The hood, on the other hand, doesn't have this, a choice that facilitates movements during the load and mouthfill management. I find the neck area slightly wide, but still acceptable for a product that is not custom-made. In the center of the hood, there is a full print with the logo. The beaver tail has a double clasp; I think this makes it a bit heavy and less streamlined. I would have preferred a single clasp or "hook and loop." However, it's rare to find standard wetsuits with a streamlined jacket and light closure.

The Sideral also features a reinforced triangle of lining at the double clasps. The jacket's print is very beautiful, centrally with a carbon-effect and silver print on the sides to match the leg section of the pants. I consider this effect very feminine and elegant. The fit around the chest circumference is well-done and comfortable.

Well, I’m ready to get in the water. Temperature: 8.5°C. I bring the atoll and we head out. The neoprene feel against my skin, compared to the wetsuit I usually use, is extremely soft. The wetsuit is much less compressive, and even on the boat, I can move easily to finish dressing.

The dive in January with water at 8/8.5°C is always quite shocking and destabilizing. I notice that the trickle of water entering is uncomfortable because I feel it coming from the hood, from my shoulders to my stomach. However, there is no issue with the wrists and ankles, where the seals stay firm and prevent water from filtering. I also notice a greater buoyancy compared to my usual wetsuit. I begin the dive on a cable at about 40 meters. As expected, the hood gives me a lot of jaw movement space, so I don’t need to put it under my chin. A bit more water enters, but this is excellent for an efficient mouthfill.

The compression of the neoprene on the body is minimal, almost imperceptible, remaining good even beyond 30 meters, and I feel excellent elastic return. I descend in free immersion and move easily with my arms both on the descent and ascent. 5mm wetsuits are rarely used in competitions in the sea, except in lakes where the Italian Championships are held, and many prefer them for the lower temperatures. I wore it during pre-competition training, but on the competition day, I opted for a 3mm wetsuit because, beyond certain depths, even the highest-quality thick neoprene can hinder performance. I stay in the water for about 30 minutes, doing two static dives at 7 meters for warm-up, a check dive for compensation, nose clip, and weights, and finally my deep dive where I encounter a slight thermocline. The beauty of the Adriatic Sea in winter (or the lake) is that the "cut" is practically nonexistent, and sometimes you encounter warmer zones at depth. Despite the time spent in the water and the first uncomfortably cold entry, I reach a stable comfort level and my body temperature stays optimal. I always recommend a 1.5mm undersuit for those who feel the cold more to keep the upper part warmer. Personally, I never wear gloves or boots, but they should definitely be considered. This thickness of wetsuit is recommended until the end of June.

Conclusions

The Sideral by C4 deserves a solid 9. For its ergonomic fit, high compression resistance, heat retention, excellent compression, and also for the carbon-effect print, which, combined with the solid-color parts, gives it a "spacey" and very feminine look.

Pros:

Very feminine model

Excellent elasticity

Non-toxic materials, phthalate and latex-free

Reinforced cuffs

Cons:

Double clasp closure

Slightly wide neck area

Significant buoyancy

Technical Specifications

Neoprene: glide skin, specifically designed for freediving in 2 pieces

Internal lining: highly elastic material; the wetsuit is glued and stitched inside

Sizes: 5