The Tern from Shearwater is a Nitrox dive computer with easy-to-understand menus. The Tern offers a bright easy-to-read display utilizing an AMOLED color screen. The Tern includes open-circuit dive modes for Air, Single gas Nitrox (up to 40%), and user selectable 3-gas Advanced Nitrox (up to 100% O2), as well as a richly featured gauge and freedive modes.