Fixture Body assemblies are semi-complete Source Four fixtures, which only lack a lens tube. Perfect for users who have plenty of lens tubes, but need a couple extra fixtures. The No Burner option is intended for users who don't have existing Source Four fixtures, but want to take advantage of the Source 4WRD LED engine.
Single clutch is for 10° and higher lens tubes
Double clutch is for 5° lens tubes, or Source Four Zoom
No Lamp Burner option is for use with the Source 4WRD LED Engine