This listing is for the big control dial that you see in the photos. I use these quite often in for my transmitters and Regenerative Receivers. You'll see them on different eBay listings.

This dial is just short of 3.25" in diameter (82mm) and about 1 inch in height. This is a 3D plastic print.

It fits a standard 1/4" shaft and comes with an L-wrench for adjusting the set screws.