REPLACEMENT TRACKBALL - Designed for any trackball mice using 1.34 (34mm) trackball size; Such as: PERIMICE-517/717, MX Ergo, M570, Cordless, TrackMan Wheel (not include Trackman Marble), M-XT3DRBK (EX-6), M-DT2URBK, EX-G/DEFT, MA-WTB43BKSMOOTH SURFACE - The surface is treated with a special coating to provide a precise and smooth tracking performanceABSOLUTE SPHERICAL - A diameter of 1.34 inches; Provides fast movements and works perfectly for multiple screen controlHOW TO REMOVE THE TRACKBALL - The trackball from PERIMICE-517/717 can be easily removed from the bottom hole of the mouse, using the tip of your fingerGLOSSY YELLOW: In a glossy yellow color; Also available in glossy red, glossy blue, glossy, purple, glossy pink, glossy lavender, and, glossy green A replacement trackball for your trackball mouse with a 1.34-inch diameter. The ball was made of high-quality material designed for major mouse brands in the market. Fits to trackball devices below: PERIMICE-517, PERIMICE-717, PERIMICE-520, PERIMICE-720,MX Ergo, M570, Cordless, TrackMan Wheel (not include Trackman Marble), M-DT2URBK, MA-WTB43BK, and more. Specifications: Diameter: 1.34-inch (34 mm) Weight: 0.06 lb (0.03 kg) Color: Glossy Yellow. Track Page Views WithAuctiva's Counter