Video - How to Guide for Using the G40 Hi, I’m the G40 Brewing System! Here’s How to Assemble and Use Me. See written instructions here. Check out our YouTube Channel here. Related articles Instructions - G40 Video - Big Brew Day 2022 My G40 sight glass doesn't always show the same measurement or appears to be off by a little bit - is something wrong with it? Video - How to Guide for Using the S40 Instructions - GC4 (Touch Screen) - Other Languages