Characteristics and Interoperability Our lightest, most feature-rich mouse to date. You have control thanks to customizable magnetic thumb buttons. It's amazing how comfortable the ergonomic shape is, and the Model I weighs only 69 g. Formulate Your Successful Combination With its modular side buttons, you can easily customize the Model I to fit your playstyle. It's simple to switch out two of the four thumb buttons to get the ideal fit for your hand. Alternatively, you can totally eliminate their usability by selecting the flat shape option. There are up to nine different combinations that you can experiment with. Ultara Light Endurance & Agility With the Model I, control in a variety of games is effortless and it becomes an extension of your arm. Its ergonomic body makes it possible to grip it with confidence and comfort while preventing hand fatigue.