Why are some shoes labeled “WP”?

Shoes marked with WP are guaranteed to be 100% waterproof. WP stands for Waterproof, and these models are designed with an inner, biodegradable polyester membrane that prevents water from getting in. The membrane contains microscopic pores that are smaller than water molecules — blocking moisture — while still allowing air to flow in and out. This makes the shoes both waterproof and breathable, ensuring comfort in wet conditions.