eproduct codeMagnification Near Visual field near Working distance ridoMED163622.5 x 75 mm350 mm ridoMED163633 x 55 mm200 mm ridoMED163644 x 35 mm250 mm Product overview [...] Telescopes and monoculars ridoMED Product PropertiesCoated lens system.Achromatic lens made of high quality silicate.Adjustment of pupillary distance of 54–74 mm.Lens diameter 23 mm.Focusing /dioptre