【Product Contents】 ◎ Bearing-type trackball case (for 25mm ball) x 1 → Shipped with 3 bearings, washers, and rear screw receiver spacers installed. By firmly attaching washers to high-precision bearings made by MinebeaMitsumi, which conform to JIS standards, and then tightening them, we have achieved a very smooth and stable rotation. The product does not include a trackball ball. ◎ Trackball case mounting screws x 2 The mounting screws we send have a head diameter of 3.8 mm and are M2x5 mm. Please check if they fit your keyboard case. Two material options are available: ① White Marble: PLA with a natural stone-like texture ② Iron Gray Metallic: PLA with the texture of a metal surface and a metallic shine (does not contain metal particles) ※ The above descriptions are quoted from the filament manufacturer's website. ☆ Please specify the material in the comments after purchase. 【Description】 ・ Bearing-type trackball case compatible with 25mm balls, usable with keyball and roBa. ・ Smoothness adjustment stability improvement by providing washers at the bearing mounting part to prevent interference between the bearing and the case, strength improvement by protecting the seating surface, and loosening mitigation measures for the mounting screws. ・ The design prevents the ball from falling out even if the case is turned upside down. ・ We have prototyped and adjusted the sensor sensitivity and the smoothness of the ball's rotation. ・ The trackballs used for prototyping and adjustment are Perixx 25mm ball, Elecom 25mm ball, and POM ball approximately 25mm. 【Other】 ・ We will check the ball's rotation by installing the ball once before shipping. ・ Made with a 3D printer. Layer lines are visible on the surface that is visible during use, and a mesh-like layer is also visible on the unseen back side. These are specifications of 3D printers, so please consider this product with the understanding that it is not an industrial product. ※ Notes on size Please refer to the image. Approximately 40.7mm from the back to the tip, and approximately 26.0mm wide. (These are approximate measurements) We will answer individual questions about the size of each part if you comment. Please check the size before purchasing. #keyball #roBa