This is not just for trackballs - I've replaced the switches on my Corsair M95 (around 8 years old) twice already. And on the cheap Dell laser mouse I'm using n

This is not just for trackballs - I've replaced the switches on my Corsair M95 (around 8 years old) twice already. And on the cheap Dell laser mouse I'm using now I had to swap the left click switch only after a year or so. Since most mice use the same Omron D2F switches I just keep a bag of spares at home.