Side slit version has 39g total mouse weight and solid side version has 41g total mouse weight PAW3950 HS sensor Nordic 52840 MCU Side buttons use Omron Blue Dots switches TTC Dust Proof Silver encoder switch Polling rate adjustable between 125-8000Hz Lift off distance adjustable to 3 different levels: 0.7mm, 1mm, 2mm 300mAh battery Max 1000Hz polling rate in wired and 8000Hz in wireless mode with 8K dongle (included)