The Apple Desktop Bus Mouse G5431, released in 1986, was one of Apple's early ADB (Apple Desktop Bus) connected mice, used with the Macintosh II, Macintosh SE, and other models. ◎ Main Specifications and Features - Model Number: G5431 (also known as A9M0331) - Connection Method: ADB (Apple Desktop Bus) port - Number of Buttons: 1 button (Apple's traditional simple design) - Color: Beige (based on Apple's "Snow White" design language) - Shape: Compact body, designed to fit in the palm of your hand - Internal Structure: Mechanical ball tracking system. Relatively easy to clean and maintain. - Compatibility: Macintosh SE, Macintosh II, Apple IIGS, and other models equipped with ADB ports - Compatibility Notes: Cannot be used with Macs that do not have an ADB port. A dedicated adapter is required for USB conversion. ◎ Historical Background and Significance - It was one of the first mice to introduce the ADB standard by Apple, representing a major shift from the previous serial connection. - It was the first mouse to adopt the "Snow White" design language, symbolizing a change in Apple's product aesthetics. - The successor model, the more rounded Apple Desktop Bus Mouse II (M2706), was released in 1993. ※ The surface (especially the top) has yellowing due to aging. ※ This item is listed as "junk" because there is no equipment to confirm its operation.