Get ready for undersea discovery with this playfully designed Invicta stainless steel men's diving watch, which features an outline drawing of an old-style diver's helmet on the white mother of pearl dial face. You'll stay confident on deep dives thanks to its water resistance to 300 meters (1000 feet). The large, round watch case is topped by a black-plated unidirectional rotating bezel with silver elapsed time markings. It's completed by a handsome stainless steel bracelet band, which is joined by a fold-over safety clasp. An automatic (or self-winding) watch is fitted with a device (rotor) that automatically winds the spring by using the force of gravity. It needs no battery, but it will stop if you have been physically inactive for an extended period of time--as long as you're moving, the watch will stay powered. Swiss watchmaker Abraham-Louis Perrelet invented the self-winding mechanism in 1770. It worked on the same principle as a modern pedometer, and was designed to wind as the owner walked. Tritnite is a luminous material with an extended glow exclusively developed by Invicta in Switzerland and added to their timepiece hands and markers. When exposed to regular daylight, it will hold its glow for about 20 hours.