Impermeable

The water column indicates the degree of impermeability of the fabric: the higher the number, the more impermeable the fabric.

Windbreaker

Not the slightest breath of wind can get in. In short, you never feel the cold wind through the fabric.

Isolated

Your body heat is maintained at a good level, even when it is very cold outside.

Breathable

This means your sweat can escape instead of being trapped, so you never feel clammy.