Orient case backs typically display the brand name or logo, caliber number, serial number, water resistance rating, and case material. The Orient logo, which has featured various designs over the decades including the distinctive twin lion emblem, can sometimes help approximate the production era. The twin lion logo is commonly associated with Orient and has appeared in several variations throughout the brand's history.
The caliber number on Orient case backs is often particularly useful for identification, as Orient is known for using proprietary in-house movements. Caliber numbers can typically be cross-referenced with collector databases and Orient's product documentation to determine the movement type, features, and approximate production period. The case back may also indicate the country of manufacture, which for Orient is most commonly Japan.
Some Orient watches feature screw-down case backs with engravings, while others use snap-on or press-fit designs. The Orient Star line typically features more elaborate case back markings and may include exhibition windows. As with all brands, case back markings should be considered alongside other identifying features, as they can potentially be altered or replaced.