*Cyelee T3-G Green Dot sight automatically turns on when you move and will automatically turn off if you don't move for 1-3 minutes. *1 CR2032 battery will last up to 50,000 hours of use with a sharp 3 MOA green dot with 10 brightness settings for visibility in all light conditions.*Rugged Design - The T3-G is a one-piece aluminum construction that is fogproof, shockproof, waterproof to 10ft.Cyelee T3 red dot sight is based on an already-proven design: the Romeo 5. It is equipped with auto power awake / off feature and easier to operate. Featuring a crisp 2 MOA red dot reticle, waterproof housing with shockproof internals. And Provides 2 base mounting options - Low Profile and Absolute Co-witness.