This is the watch used by all branches of the U.S. military for its rugged design and unique 25-year illumination technology. Also favored by law enforcement, it uses the same luminescent technology implemented for U.S. Navy SEAL watches for clandestine operations--tiny glass capsules lined with phosphorous and filled with tritium gas. Built into the index and hands, each capsule fluoresces when the two materials react, eliminating the need for an external light source. Made of solid 316L stainless steel that withstands the rigors of training, both the locking, screw-down crown and case back provide water resistance to 656' while a ratcheting unidirectional bezel ensures accurate elapsed time reading for underwater activities. Swiss quartz movement provides precise, reliable timekeeping. The carbon fiber dial and face are protected by a reflection- and scratch-resistant sapphire crystal. The watch's lithium battery provides up to 10 years of operation before requiring replacement. The adjustable 3/4"-wide stainless band (jeweler only) fits wrists 3" to 9 1/4". 1 3/4" Diam. x 1/2" D. (8 oz.)