We've always loved Kask helmets for their superior comfort and quality, so we're happy to see they've entered the world of gravity mountain biking with the Defender full-face helmet. It features a full carbon shell with 18 large ventilation ports, making for a strong, lightweight, well-ventilated helmet with full ASTM downhill race certification. The chin guard provides comprehensive coverage, and uses a replaceable foam air filter that preserves airflow while guarding against dust and debris.