logitech g502: where the hell is the serial number?

my left mouse button has started to double click instead of single click and i want to submit a rma request but can’t find its serial number on the unit itself. i know more than a handful of you qt3ers have this model as well.

I have a G502. It’s on a sticker at the end of the USB cord, where you plug it in to the PC.

thanks. no wonder i couldn’t find it.