The ergonomic design of the Nikon Aculon 10-22x50 binoculars combines smooth fingertip zoom control, a lead- and arsenic-free Eco-Glass lens and Turn-and-Slide rubber eyecups that make it easy to achieve correct eye positioning. Lead and arsenic-free Eco-Glass. Aspherical eyepiece lenses help deliver a flat field of view. Lens multicoating enhances image brightness. Tripod adapter included.