Kensington Pro Fit Ergo Vertical Wireless Trackball Mouse, Black (K75326WW)
Billiard Ball Finds A New Home In Custom Trackball Mouse | Hackaday
CST LTRAC Pool Ball Swap Mod
Trammell Hudson ✪ on Twitter: "New trackball with a 57.2mm ball, which means it works perfectly with a standard sized (non-UK) billiard ball. https://t.co/ewLjHGM2Yi" / Twitter