Fourth Element Xerotherm Set Review
Last updated: July 2025
- Lightweight warmth: Ideal base layer for low 60s°F dives
- Seal-friendly fit: Smooth against drysuit seals
- Layer-ready: Pairs under Arctic for colder water
- Breathable: Comfortable even on hot days
- Premium price: Costly for the warmth offered
A premium base layer for drysuit diving in moderate temperatures. Lightweight, streamlined, and surprisingly warm for its thickness, but the price is hard to ignore.
Pros & Cons
| Pros | Cons |
|---|---|
| Excellent base layer for low 60s °F dives | Expensive for what it is |
| Smooth fit under drysuit seals | Less warmth than other options at same price point |
| Layers easily with Arctic for cold water dives | Hard to justify if not layering or brand-matching |
| Comfortable and breathable even on hot days |
Why I Chose the Xerotherm
I already owned the Fourth Element Arctic and found it too hot during Chicago’s summer quarry season. I wanted something lighter and more breathable for dives in the low 60s. The Xerotherm filled that role well. I also liked that I could layer it under the Arctic if I wanted to dive into much colder water like Lake Michigan later in the season.
Since I was already using the Arctic, staying within the Fourth Element line made sense. But to be honest, I’m not convinced the Xerotherm delivers enough value to justify the price if you’re not committed to brand consistency. It works, and I like it, but I’m not sure it’s essential.
Verdict
The Xerotherm is a well made, purpose built underlayer. If you dive dry in moderately cold water and want something lighter than a full insulation suit, it’s a strong option, especially if you plan to layer or already own other Fourth Element pieces. But if you're looking at value alone, there may be other base layers that perform similarly for less.
Would I buy it again? Probably, but only to stay within the Fourth Element ecosystem.
Who the Xerotherm Is Best For
This item is best suited for:
- Drysuit divers in low 60s°F water needing a breathable base layer
- Divers who want to layer with the Arctic for colder dives
- Fourth Element fans seeking consistent gear system
It may not be ideal for:
- Divers wanting maximum insulation per dollar
- Warm-water divers without layering needs
Deep Dive into the Score
Scoring System: Each category is scored out of 10 and weighted by importance. This model is used consistently across all gear reviews for transparency.
| Category | Score | Raw Score | Weight | Weighted |
|---|---|---|---|---|
| Function & Performance | Strong | 8.0 | 30% | 2.40 |
| Ease of Use | Exceptional | 9.0 | 20% | 1.80 |
| Versatility | Strong | 8.0 | 15% | 1.20 |
| Durability & Build Quality | Exceptional | 9.0 | 15% | 1.35 |
| Value | Fair | 6.0 | 10% | 0.60 |
| Brand Trust & Transparency | Exceptional | 9.0 | 10% | 0.90 |
| Total | 8.25 / 10 | |||
Rounded Display Score: 8.3 / 10 — Strong
Deep Dive Score Explanations
- Function & Performance – 8.0: Keeps me warm down to the low 60s. Anything colder and I need to add layers.
- Ease of Use – 9.0: Easy to don and doff. No interference with drysuit seals or valves.
- Versatility – 8.0: Works on its own or under other suits. But doesn’t stretch well into colder temperature ranges.
- Durability & Build – 9.0: After repeated use and washing, it shows no signs of wear or sagging.
- Value – 6.0: It’s expensive, and for some divers, that price won’t make sense given the limited warmth on its own.
- Brand Trust – 9.0: Fourth Element continues to deliver premium dive wear with consistency and support.
Performance in the Water
- Temperature Range: Works well on its own in the low 60s Fahrenheit. Below that, I switch to the Arctic or add layers.
- Fit & Flexibility: No bulk issues. It wears close to the body and doesn't interfere with seals or drysuit movement.
- Layering: Designed to work under other undergarments like the Arctic. Comfortable and breathable even in warm weather.
- Comfort: No itch, no odor issues, no bunching or pressure spots after repeated dives.