I'm selling my CST trackball, model CST2545-5XW-RC.
It's the sought-after 3200 dpi model with the possibility to connect two external switches. Condition is excellent because it saw very little use. It comes with original packaging and original software on CD. I dropped in a carom billiards ball (perfect fit) but will also include the original black ball.
Asking price is 200 EUR O.B.O. + shipment. Note that this 3200 dpi model is not being made anymore, and it's about the same I paid some time ago (first owner).