HD Optical System delivers exceptional resolution, cut chromatic aberration and provide outstanding color fidelity, edge-to-edge sharpness and light transmission; Anti-reflective coatings on all air-to-glass surfaces provide increased light transmission for greater clarity and low-light performance; Ultra-hard, scratch-resistant ArmorTek coating protects exterior lenses from scratches, oil and dirt; O-ring seals prevent moisture, dust and debris from penetrating for reliable performance in all environments; Compatible with a tripod adapter, allowing use on a tripod or car window mount; HCD Corrected Shoot-To Range Reticle