The Rolex Submariner 5513, particularly the military variant produced circa 1973, is a remarkable timepiece that embodies the spirit of exploration and durability. This model is characterized by its robust stainless steel case, measuring 40mm in diameter, and its unidirectional rotating bezel, which is essential for divers to track elapsed time underwater. The matte black dial features luminous hour markers and hands for optimal visibility in low-light conditions, a crucial feature for military applications. This particular version is known for its clean, utilitarian design, often lacking the date function, which enhances its legibility and simplifies its operation.