The Leica Duovid 8/12x42 are the first premier binoculars that feature switchable magnifications. This makes it a master of the various tasks of travel placed upon a binocular, giving either steady images and tons of light or awesome pulling power as needed.

Specifications: 

Weight: 37oz
Dimensions: 423/32 x 63/16 x 221/32 in
Eye Relief: 14.5mm
Field of View: 351 ft/268 ft
Exit Pupil: 5.25mm/3.5mm
Objective Diameter: 42mm
MPN: 40400