Designed for the slopes and the street, the Sentry Prime Sigma offers high-contrast optical clarity and quick lens-swap convenience so you stay focused, no matter the light conditions. Fit: Large (Adult) Lens Technology / Contrast: SIGMA lens system enhances color and terrain contrast in snow conditions Lens Change System: Magnetic lens attachment with mechanical latch for quick and secure swaps Field of Vision: Wide cylindrical lens with optimized peripheral visibility Ventilation & Comfort: Airflow system combined with triple-layer face foam for anti-fog performance and all-day comfort Helmet Compatibility & Strap: Helmet-compatible frame with silicone-backed adjustable strap Accessories: Includes spare lens and protective storage bag