The XTRFY M4 has an optical sensor with a wide CPI range. However, there’s no customization software, so you’re only limited to preset sensitivity settings, which you can cycle through with the button on the underside of the mouse. There are eight different presets: 400, 800, 1200, 1600, 3200, 4000, 7200, and 16000. The LED light next to the button changes color to indicate the current setting. There’s also a physical switch on the bottom to adjust the polling rate; you can set it to 125Hz, 500Hz, or 1000Hz.