The one I have is from Racers Edge, available direct or through Stormer Hobbies. It works with both standard laydown or standup brush hoods for under $20. The ideal way to use it is first test the brushes so see how they are wearing, then only adjust (twist) the hood that requires alignment. Trinity, Niftech, Parma (PSE) and a few others sell variations but some are more costly or other styles do not allow for individual alignment of each brush hood.
Trinity and Racers edge are the best. I had a parma and did not like it at all.
If used properly it frees up the armature in the can and takes out any binding - make sure to check before during adn after tightening the screws and brush posts. You might think you have a sweet deal then tighten it and see that it tweaked the arm and it binds up.
Well worth the investment plus you do not know how many people are going to want to borrow the tool.