WHAT DO THE NUMBERS MEAN?
| Wp (Water Penetration Resistance) (Unit: mmH2O) |
Function |
| Class 1: >1500 mmH2O | Minimum British standard for a jacket to be called Waterproof. *Good for ski, snowboarding, London rain |
| Class 2: 15000-20000 mmH2O | Can resist Heavy rain, snow. But it will soak through overtime. *Proper waterproof for downpours |
| Class 3: >20000 mmH2O (e.g. Gore-Tex) |
Can resist all conditions, even carrying heavy load. *Mountain concurs, sailing |