Certina case backs typically display the brand name and logo, including the distinctive turtle emblem that represents the DS (Double Security) concept. This turtle logo is one of Certina's most recognizable symbols and is commonly found on the case back of DS-certified models. The presence and style of the turtle logo can help confirm that a watch is from the DS line and can sometimes provide clues about the era of production.
Additional case back markings commonly include the serial number, model reference, caliber number, water resistance rating, case material, and 'SWISS MADE' inscription. Certina's DS models often feature enhanced case back construction as part of the Double Security system, which may include reinforced case backs and additional gaskets. The specific water resistance rating is particularly relevant for Certina's sport and dive models.
Vintage Certina case backs from the pre-Swatch Group era may display different marking styles and formats. Earlier watches may feature more ornate engraving, period-specific logo designs, and hallmarks related to the case material. The DS concept was introduced in 1959, so watches from before that date would not carry DS-related markings. As with all vintage watches, case back markings should be verified against the movement and dial for comprehensive authentication.