It is the zoom model binoculars,which specification is as follows: Amplification Rate:9x-25x Objectlen Diameter:25mm Angel of view:3.7degrees-1.8degrees. Exit pupil Diameter:2.5mm-0.83mm Exit pupil distance: 8.5mm-7.0mm Weight: 330g Product size: 115mmx145mmx118mm More designs with Zoom are available,please go to our websit to select more.