Waterproof Breathable Membranes with 37.5® Active Particle Technology
Built to Breathe. So You Stay Dry from the Inside Out.
When you want to stay dry, waterproof isn’t enough.
Staying dry means stopping moisture from getting in and preventing sweat from building up next to your skin.
Humidity is an amplifier, making hot feel hotter and cold feel colder.
Membranes with 37.5 Technology are the only membranes fused with natural active particles, shown to speed moisture vapor transmission by up to 38%* and remove sweat before you get uncomfortable.
It’s more than a WPB membrane — it’s a game-changer for comfort, safety, and performance in all conditions.
When you want to stay dry, waterproof isn’t enough.
Staying dry means stopping moisture from getting in and preventing sweat from building up next to your skin.
Humidity is an amplifier, making hot feel hotter and cold feel colder.
Membranes with 37.5, Thermoregulation Technology use natural volcanic minerals to speed moisture vapor transport by up to 38%*, removing sweat before you get uncomfortable.
It’s more than a WPB membrane — it’s a game-changer for comfort, safety, and performance in all conditions.
STAY DRY FROM THE INSIDE OUT
Up to 38% faster moisture vapor transmission to prevent sweat build up during activity and that cold, clammy feeling when you cool down.
WARMER WHEN IT’S COLD, COOLER WHEN IT’S HOT
Responds to and helps balance your body’s temperature and humidity - unlike standard membranes that trap heat and moisture.
NATURAL BREATHABILITY
Mineral-based and permanently embedded – not a chemical treatment. These ultra-porous minerals massively increase surface area to remove trapped moisture.
Testing That Redefines How Waterproof Products Keep You Dry.
Moisture Vapor Transmission Rate (MVTR) is the key measure of how efficiently materials move
moisture out of a garment. A higher MVTR means faster moisture release, directly increasing comfort.
TESTING
Three waterproof breathable laminate fabrics were tested under ASTM E96-B (upright cup) and ASTM
E96-BW (inverted cup) to determine differences in MVTR values.
- Sample 1 – Fabric + Laminate, No Print Layer (KN292-2L)
- Sample 2 – Fabric + Laminate + 37.5 Active Particle Print Layer (KN292-2.5L 37.5)
- Sample 3 – Fabric + Laminate + non-37.5 Print Layer (KN292-2.5L non-37.5)
ASTM E96-BW results also showed Sample 2 with 37.5 Technology to have the highest MVTR value –
29% increase over Sample 3 and 10% increase over Sample 1.
FINDINGS
- Adding 37.5 Active Particle Technology to the print layer of a 2.5-layer fabric increased MVTR by 38% over the 2.5L fabric without 37.5 Technology**
- The 2.5-layer fabric with 37.5 Active Particle Technology delivered a higher MVTR than the 2-layer fabric without 37.5 Technology.
- The MVTR value dropped significantly when 37.5 Technology was not included in the print layer.
- Full test reports for both ASTM E96-B and ASTM E96-BW available upon request.
THE BOTTOM LINE? WATERPROOF BREATHABLE MEMBRANES WITH 37.5 TECHNOLOGY PROTECT YOU FROM THE ELEMENTS WHILE LETTING YOUR SWEAT ESCAPE FASTER.
*Based on 3rd-party ASTM E96-B testing. ASTM E96-BW testing results shown below graph above.
**Test results may vary. MVTR for products with 37.5 Technology have shown up to a 118% increase depending on fabric construction and test method.
Next Gen Membrane, Next Level Comfort. No Tradeoffs.
Next Gen Membrane, Next Level Comfort. No Tradeoffs.
