These units are roughly the same size and form factor as their fixed siblings, but with significantly lower light output. After installing 5 fixed 4" Lithonia discs, each producing 750 lumens, the 2 pendant lights I installed on the adjacent vaulted ceiling were disappointing: only 680 lumens - about as much light as a standard 65w R30 -Luminaire without halogen. I think I should have used a 6" bulb for this application, but why can't Lithonia make a 4" gimbal version with the same 750 lumens?