KELVIN C1 · Cryo Cradle · Gen 1

Sauna hot.
Sperm cold.

A phase-change cradle that holds 13°C for forty-two minutes, so ninety degrees of dry heat stops being a fertility decision.

Add to bag, $88 Why it matters

13°Ccontact hold
42minfrom freezer
186gloaded weight

C1 / Bone · Glacier

Product

Four decisions, nothing else.

The science

Testes run 2 to 4°C below body temperature. That gap isn't decoration.

−2 to 4°C

Normal scrotal temperature relative to core. Sperm production is tuned to that window and falls off outside it.

15 min × 2

In a 2013 Italian study, healthy men taking two fifteen-minute saunas a week for three months showed significantly reduced sperm count and motility.

~6 months

Roughly how long those men needed to return to baseline after stopping. Reversible, but slow, and a bad thing to discover on a deadline.

Bench simulator

15 min on the top bench at 90°C

Without

37.4°C

With KELVIN

33.1°C

Illustrative model, not clinical measurement. KELVIN is apparel, not a medical device, and it doesn't treat or prevent anything. Talk to a doctor about fertility.

Study: Garolla et al., Human Reproduction, 2013, on sauna exposure and human spermatogenesis.

Spec sheet

C1, on paper.

Origin

Where the idea came from.

The whole thing started as a jelly. Here it is, unedited.

Campaign

Five Instagram concepts.

Launch set. Tap a card for the caption and the call to action.

Gen 1 · limited run

KELVIN C1

$88 free shipping / 60-night trial

Ships in a bone-white box with one spare liner. Freezer-ready out of the sleeve.