HONEST COMPARISON
Buttercloth Underwear vs IcedBallz: Mint Fibers vs Real Ice in the Sauna
Buttercloth is a Shark Tank favorite with “Icy Cotton” infused with mint fibers. It feels cool when you put it on — but what happens when you step into a 90°C sauna? We break down the science and the real-world performance.
What Is Buttercloth Underwear?
Buttercloth is a men’s clothing brand founded by Dan Koch, who pitched on Shark Tank and secured a deal with Robert Herjavec. Their underwear line features “Icy Cotton” and “Icy Bamboo” fabrics that are infused with natural mint fibers through a patented process. The result is a fabric that feels noticeably cool to the touch at room temperature.
At $32 per pair (or about $29 per pair in a 3-pack for $86), Buttercloth underwear is positioned as a premium everyday option. They emphasize 6-way stretch, moisture-wicking, antibacterial properties, and a cooling sensation from the mint fibers. Reviews consistently praise the softness and comfort for daily wear.
Buttercloth Underwear at a Glance (May 2026):
- •Price: $32/pair or $86/3-pack
- •Material: Icy Cotton or Icy Bamboo with mint fibers
- •Cooling method: Mint-infused fabric (no ice pack)
- •Cooling duration: Sensation fades within 60 seconds in a sauna
- •Special feature: 6-way stretch, antibacterial, Shark Tank brand
- •Sauna-specific: No — designed for everyday wear
- •Ice pack included: No
The Problem With “Cooling Fabric” in a Sauna
Here’s the thing about mint-infused fabric: the cooling sensation works through a chemical reaction with your skin’s thermal receptors. At room temperature or during light activity, it creates a noticeable cooling feel. But a sauna operates at 70–100°C (158–212°F). At those temperatures, the mint fiber effect is completely overwhelmed by the ambient heat.
Think of it this way: mint lip balm feels cool on your lips at room temperature. But if you stuck your face in an oven, you wouldn’t feel the mint anymore. The same principle applies to Buttercloth in a sauna — the fabric cooling effect lasts approximately 30–60 seconds before the extreme heat takes over completely.
This isn’t a knock on Buttercloth as a product — it’s excellent everyday underwear. But it was never designed for sauna use. There’s a fundamental difference between “fabric that feels cool” and “active thermal cooling with a frozen ice pack.”
Buttercloth vs IcedBallz: Side-by-Side
| Feature | Buttercloth | IcedBallz |
|---|---|---|
| Price | $32/pair | $69 (underwear + ice pack) |
| Cooling Method | Mint fiber fabric | Frozen ice pack in pocket |
| Cooling Duration (Sauna) | <1 minute | 45–60 minutes |
| Ice Pack Included | No | Yes (anatomically shaped) |
| Sauna-Specific Design | No | Yes — built-in pocket |
| Material | Cotton + mint fibers + spandex | Premium cotton |
| Fertility Protection | None | Active cooling protects sperm |
| Best For | Everyday comfort | Sauna & heat therapy |
| Cost-per-Minute of Sauna Cooling | N/A (no active cooling) | $1.15–1.53/min |
Where Buttercloth Wins
To be fair, Buttercloth has genuine strengths — just not for sauna use:
- •Incredible softness: The 6-way stretch fabric genuinely feels like butter — reviews are unanimous on this
- •Shark Tank credibility: Legitimate brand with real investment backing
- •Antibacterial: Mint fibers naturally inhibit bacteria — great for all-day wear
- •Affordable: At $32, it’s a reasonable premium underwear choice
- •Everyday cooling: The mint fiber effect works well for office, gym, and casual wear
The Sauna Dealbreaker
In a sauna environment, passive fabric cooling simply cannot compete with active thermal cooling. When the ambient temperature is 90°C, your body is absorbing heat from all directions at an enormous rate. A mint-infused fabric might make you feel cool for the first minute, but once the fabric itself heats up to body temperature (which takes seconds in a sauna), the cooling sensation is gone.
An ice pack, on the other hand, is a thermal reservoir. It actively absorbs heat from your body for 45–60 minutes because it has to undergo a phase change (ice to water) to warm up. That’s thermodynamics working in your favor — no fabric technology can match the heat absorption of a frozen ice pack.
The Bottom Line
Buttercloth is genuinely excellent everyday underwear. If you want soft, premium boxer briefs for daily life, it’s a great choice. But if you’re buying underwear specifically for sauna use and expecting cooling protection, you need active ice pack cooling — and that’s exactly what IcedBallz delivers for 45–60 minutes per session.
Frequently Asked Questions
Can I wear Buttercloth underwear in the sauna?
You can, but you won’t get any meaningful cooling. The mint fiber effect is designed for room-temperature comfort. In a 90°C sauna, the fabric will heat up within seconds and feel like any other pair of underwear.
Does Buttercloth protect fertility in the sauna?
No. Without active cooling (an ice pack), the fabric does nothing to reduce testicular temperature in a sauna environment. Studies show that sustained heat exposure can reduce sperm quality by up to 50%. Active cooling is the only proven method to mitigate this.
Is Buttercloth or IcedBallz better value?
They serve different purposes. Buttercloth ($32) is excellent for everyday wear. IcedBallz ($69) is purpose-built for sauna and heat therapy. If you sauna regularly, IcedBallz provides active cooling that no fabric technology can match.
Could I use Buttercloth AND IcedBallz together?
IcedBallz includes its own premium cotton underwear with a built-in ice pack pocket. You don’t need separate underwear. But many customers wear Buttercloth for daily life and switch to IcedBallz when it’s sauna time.
Ready for Real Sauna Cooling?
Don’t rely on fabric sensations that fade in 60 seconds. Get 45–60 minutes of active, ice-powered cooling with IcedBallz.
Order IcedBallz — $69 →Shipping: $6.95 US / $5.95 EU & worldwide · 30-day guarantee