The Astra IIIB has somewhat revolutionized celestial navigation. Never before has such a high quality, accurate metal sextant been available at such a low price. Over 10,000 sextants of this model have been sold in the US alone in the past 13 years. The Astra IIIB is made from lightweight aluminum alloy which resists corrosion. It is electrically lighted by LED on the arc and drum by two standard size AA batteries (not included) and its low price, excellent optics makes it the perfect selection for beginners and professionals. It comes in a varnished wooden case with an instruction book, certificate of accuracy, vial of oil and adjusting wrench. Also included is a 3.5 X 40 inch monocular telescope as standard equipment.