Pentax 8-16x21 UCF Zoom II w/Case With a magnification range from 8X to 16X, the 8-16X21 UCF Zoom II binocular gives you incredible zooming ability with the convenience of a compact design. As with other UCF models, the 8-16x21 UCF Zoom II has an innovative dual-axis eye-distance adjustment system, high-refraction BaK4 glass prisms, multi-coated optical elements, and aspherical lens elements incorporated into the eyepiece optics. This portable, compact, user-friendly binocular is perfect for the viewer on the go - whether it be bird watching, sporting events, wildlife or indoor performance viewing. Features Magnification power ranges from 8 to 16x21. Aspheric lens elements enhance edge-to-edge sharpness. In-line control system positions zooming, focusing and diopter adjustment together. High-refraction BaK4 glass prisms for brighter, clearer image. Pop-out right diopter adjustment knob. Protected by a limited lifetime warranty. Magnification power ranges from 8 to 16x21.. Aspheric lens elements enhance edge-to-edge sharpness.. In-line control system positions zooming, focusing and diopter adjustment together.. High-refraction BaK4 glass prisms for brighter, clearer image.. Pop-out right diopter adjustment knob..