These zoom binoculars provide a magnification range of 7x to 21x. The optical design of this instrument is based on Porro prisms. The lenses are made of BK-7 glass and are completely multi-coated. This minimizes light loss; The instrument transmits a sharp, bright image with vivid colors.The interocular distance is adjustable in a range of 58-72 mm, diopter adjustment is available. You can quickly adjust the sharpness of this optical tool by turning a central focus wheel.The binoculars feature foldable rubber blinkers. Aluminum body with embossed rubber coating; This provides a secure grip ensuring that this optical instrument will not slip out of your hands. You can mount these binoculars on a tripod: there is a special screw bushing on the body.Equipped with a black canvas case with shoulder strap. Water resistant. Height 15 cm. Width 17.5 cm. Made in the USA.Gross weight: 970 grams.