Air Sander Controller

I use random orbital air sanders for much of my woodturning sanding.Often, I want to slow down the sander rpms but with my Grex sander, the control trigger is either off or completely on, i.e., either zero or max rpms.Iím unable to modulate or slow down the sandpaper speed.My solution was to install a small, in-line, air flow regulator between the sander and the air hose connector.

The regulator is a Titan Tools #19442 ordered from Amazon for $11.