Building on the success of the original Ultravid HD, Leica's 10x42 Ultravid HD-Plus Binoculars add improved technologies and materials to create an optical device with bright and clear images across the entire field of view. The HD-Plus binoculars deliver enhanced contrast and true color fidelity, with virtually zero distortion, even in low-light conditions. Helping compensate for the visually distracting hand shake common with using 10x and greater optics, is a wide 63 apparent viewing angle. This allows the use of high-magnification binoculars without the need for stabilization equipment like harnesses or tripods. Leica upgraded the glass to specially formulated SCHOTT HT glass, which increases light transmission especially in the blue-violet light band, improves color fidelity, and enhances low-light performance. Scratch- and abrasion-resistant High Durable Coating (HDC) and hydrophobic AquaDura coating on the outer lenses protect surfaces and cause water and oil to bead off for easier cleaning and clearer vision. The roof prisms feature P40 phase correction and proprietary High Lux System (HLS) coatings. These coatings virtually eliminate chromatic aberration for enhanced color rendition and increased contrast. Complementing the optical performance are uncompromising construction details. To reduce user fatigue during long glassing sessions, the chassis is made of a lightweight yet durable magnesium alloy, with a titanium center hinge axle. The optical tubes are nitrogen filled for fogproof performance and sealed to make the binoculars submersible to 16.4' or 0.5 bar of pressure. Ergonomic thumb indents on the bottom of the binoculars, coupled with protective rubber armoring, provide a comfortable slip-resistant grip. A lubrication-free focus system provides fast and precise focusing, with PETP-Discs to provide smooth movement throughout the broad operating temperature range. Optical Performance 10x magnification 42mm objective lens diameter Compact roof prism optical path High-quality SCHOTT HT glass increases light transmission, especially in the blue-violet band, improves color fidelity, and enhances low-light performance P40 and proprietary High Lux System (HLS) prism coatings High-temperature plasma lens coating depositing system for precise optical coating placement Phase-corrected prisms reduce chromatic aberration for enhanced color rendition Scratch- and abrasion-resistant High Durable Coating (HDC) and hydrophobic AquaDura coating on outer lenses protect surfaces and cause water and oil to bead off lenses for easier cleaning and clearer vision in bad weather Use and Handling Lubricant-free center focus system with PETP-Discs provides smooth movement throughout the operating temperature range 4 right-eye dioptric correction Locking center diopter adjustment wheel Twist-out two-stage click-stop eyecups Flip-down tethered objective lens caps Tripod mountable with optional adapter Construction Details Light and durable magnesium chassis Titanium center hinge axle Slip-resistant protective rubber-armored body Nitrogen filled, fogproof and watertight to 16.5'/0.5 bar pressure Broad -13 to 131 F operating temperature Ergonomic thumb rests for added comfort and a better grip