Zeno Watch is an independent Swiss watchmaker established 1868, but the Zeno name has been in use only since 1922. Based in Basel, Switzerland, the company is known for their aviation watches. The first Zeno watches were made in 1922. Each piece was marked with a Swiss cross on the back of the casing. In 1949, the Zeno watches were exhibited for the first time at the Swiss Watch Fair in Basel. Zeno's best known watches are their "Pilot Classic" series. The range of products extends from mechanical to quartz technology wrist watches with analogue displays, collectors' wristwatches, pocket watches and sport chronographs in every combination of materials. Zeno has enlarged their successful Pilot watch family of products. Since 1999, they have produced a huge range of pilot watches in new sizes, and many COSC certificated chronometers. Zeno also makes diving watches used by the Swiss Army for their frogmen, with models rated for up to 300 meters (1000 feet) depth.