RE ZRO is G-Form's eco-friendly technology; impact protection that is fully biodegradable and 100% recyclable Pad is pre-curved (ergonomic fit), thin, flexible, and strong Guards have abrasion-resistant covering, and a wide, silicone-printed gripper to keep in place Compression mesh on the lower interior panel provides support and airflow Two-piece construction on the interior of the sleeve allows for friction-free, full range of movement Removable RE ZRO pad is hand-wash, fabric sleeve is machine-wash. Knee Guard Terra XXL