The Steiner M1580 is for visual efficiency extended-viewing comfort and object detail. The massive 80mm objective lenses and unmatched Steiner quality deliver far superior low-light performance and image acuity for artillery teams SEAL missions surveillance missions air traffic controllers forest fighters and naval patrols. Floating Prism System uses flexible silicone lens mount to absorb severe shock impact and abuse without damage Multi-Coated Optics are state-of-art for brighter picture higher contrast and sharply contoured images with natural color definition Sports-Auto Focus System lets you focus each eyepiece to your vision once then keeps images razor sharp from 20 yards to infinity Makrolon housing is durable polycarbonate with NBR Long Life rubber armoring creating a lightweight rugged chassis that withstands 11 Gs of impact. Includes tripod mount neck strap objective cover and rain protection cap.