logicool ERGO M575 This is a trackball mouse from Logitech. It offers comfortable operability. - Brand: logicool - Model Name: ERGO M575 - Type: Trackball - Color: Black Thank you for viewing. I used it for about 2 years. I replaced it with a new one because the left click stopped responding, but now I can use it again. I would appreciate it if you could understand that there is a possibility that it may become unusable again, as the cause of the left click malfunction is unknown.