The 10x42 knight ED binocular from Snypex features extra-low dispersion (ED) glass and dielectric-coated phase-corrected bak4 roof prisms that work together to virtually eliminate chromatic aberration and produces images with true color fidelity across the entire field of view and enhanced contrast. Complementing the glass and prisms are anti-reflection fully multicoated optics that improves light transmission for bright and clear images, with greater low-light performance. The objective lenses are designed in a 3-group/4-element configuration and the eyepiece lenses in a 5-group/6-element configuration to precisely control the light path the knight's open-bridge design helps to reduce weight without sacrificing strength, and provides a large surface area to hold. Rubber armoring helps to give protection from drops and impacts while helping to provide a non-slip grip. Designed for durability, the lightweight magnesium-alloy housing is nitrogen-filled and O-ring sealed for fog proof performance and makes it submersible to 3.3ft for up to 15 minute's. The twist-up eyecups provide a custom-fit eye relief for use with or without eye-wear.