Perixx 34mm trackball with matte, textured finish. Purchased on Amazon in March 2025, but selling because the feel wasn't right for me. Used for only about 2-3 hours, so it's practically new. Compatible with PERIMICE-517/717/520/720, Logitech M575/M570. Works fine with MX ERGO S. The last photo is an example of it installed. Please purchase only if you understand this.