Leupold BX-1 McKenzie HD 10x42 BinocularsLeupold BX 1 McKenzie HD 10x42 Binoculars are the next generation of McKenzies. They feature Leupold's Advanced Optical System which provides increases in resolution, clarity, and glare reduction. The McKenzie's body is waterproof and nitrogen purged. Previous McKenzie binoculars had eyecups that were permanently attached and had to be sent in for repair. The HD model has removable eyecups that can be replaced in the field if they get damaged.