Excellent for celestial observation as well as terrestrial surveillance. Can be used for viewing comets, star clusters, nebula etc. and for terrestrial subjects. These binoculars, with their massive 100mm objective lenses (and BAK-4 prisms) offer nearly the biggest field of view of any binoculars currently on the market. Choose between 20x and 40x magnification. For astronomical use, can be raised to about 45º from horizontal. Interchangeable 1.25" eyepieces; comes with aluminium carry case.