I’m using a Leopold FC900R with blues (click-thock forever!) that I got a few years back. It’s a full sized, 104 key, no RGB, no bells and whistles type deal. I got a really good deal on one (~$80 USD), but I’m in Korea where they’re made, so YMMV. I honestly don’t know what the back plate is made of, but it is quite heavy. 1.2 kgs (2.6 lbs) according to this place.