Benrus Type 1 - Sterile US Military

"Sterile" Issue

Manufactured by the Benrus Watch Co, Type I watches were issued to CIA, Navy Seals and other Special Forces units during the Vietnam war and through the late 70s. The "sterile" issue differs from the more common Types I and II watches by the fact that it has no military issue engravings on the case back. Other than the serial number, no other markings can be seen on the watch. It is thought by many that the "sterile" watches were issued to covert operators. This lack of identification on the watch would maintain a level of deniability in the event the soldier was captured during a covert operation.

Another less exotic (but probably more believable) theory regarding these "sterile" watches is they were unmarked prototypes issued for testing prior to regular production.