SENTRY PRIME SIGMA (and EXTRA LENS)Flawless wide vision, impeccable, stand out style. Perfectly balancing a cool street style vibe with the best goggle tech, Salomons Sentry Prime are goggles youll always want on. The two magnetic, color amplifying SIGMA lenses let you enjoy flawless vision in different conditions. Its super easy to pull a lens off, click another one on, secure it with the latch and go as hard as you want to go.