The Ultima DX Series features new design improvements such as a waterproof body, shock resistant rubber covering, and twist-up eyecups. They provide superb image quality with BAK-4 prisms and fully multi-coated optics. Ultima DX binoculars are super lightweight for their aperture size and all have long eye relief for comfortable viewing. Their excellent depth of field provides a good overview without the need for constant refocusing. All models are tripod adaptable and are excellent for long distance viewing whether for action sports, nature and wildlife viewing, or for astronomical observation.