Caldera Roof Binoculars, by Kruger Optical, were engineered for performance. Designed with an innovative eyepiece, these binoculars enjoy an ultra-wide field of view with superb image quality. ED glass, BBAR coatings and phase-coated Bak-4 prisms create a vivid, true image. A patented, single-hinge ergonomic design allows for easy one-handed use, even with gloves. Made from cast magnesium and easy-grip rubber armor, these binoculars are rugged and lightweight.