Sporting an ultra-wide field of view, long eye relief, and wide exit pupil—all in a compact magnesium housing—the Swarovski 10x42 NL Pure Binoculars also combines extra-low dispersion (HD) glass elements and a range of proprietary optical coatings to create a set of glasses that delivers impressive image quality and durability. In keeping with its tradition of high-performance optics, Swarovski uses highly reflective roof prisms and fully multicoated fluorite-containing HD glass lenses to deliver superior image quality. A field-flattener lens system complements the glass and coatings to keep the edges of the view crisp and sharp. The resulting views are rich with detail and saturated with lifelike colour with exceptional contrast and resolution.
In addition to its high-transmission optical system, Swarovski also equips the NL Pure binocular with a range of features that improve the handling experience. A re-engineered bridge and focus system provide smooth movement in a short configuration, so you have more of the optical tubes to grip. Covering the magnesium-alloy housing is Swarovski's iconic rubber armouring that provides impact protection and a positive grip where they are needed most. The housing is nitrogen-filled and O-ring sealed to be waterproof to a depth of 3m, and resistant to internal fogging. 
Optical Performance
Moderate 10x magnification brings subjects in close for observation while preserving the ultra-wide field of view, comfortable exit pupil, and exceptional eye relief
42mm objective lenses draw in the light required to extend its use in challenging conditions without being too bulky or heavy
Compact roof prism light path keeps the optical tubes thin for easier handling and packing
Field-flattener lenses eliminate spherical aberration & edge distortion and correct off-axis comas & astigmatism for crisp and sharp images across the entire field of view
HD Optical System: Fluorite-containing glass virtually eliminates chromatic aberrations to enhance color fidelity and brightness
SWAROBRIGHT, WAROTOP, SWARODUR coatings
Ultra-wide 69° apparent angle of view presents sweeping views of the scene in front of you, providing an immersive and near panoramic observational experience that requires very little head movement to see everything
Spacious 477-foot field of view at 1000 yards
Proprietary Swarovski Lens Coatings:
Highly reflective SWAROBRIGHT mirror prism coating optimizes color fidelity, contrast, and resolution
Anti-reflection SWAROTOP lens coating reduces glare and improves contrast
Scratch-resistant SWARODUR lens coatings protects the lenses to ensure views remain crisp and sharp