The ARRI M18 is often called the most useful HMI ever made. It became a staple on commercials, dramas, documentaries, and indie features.
The M18 is an 1,800-watt HMI daylight fixture using ARRI's lensless MAX Technology reflector. Instead of swapping PAR lenses, you focus the beam with a knob, adjusting from roughly 20° to 60°. It produces more than 70% greater output than a traditional 1.2K PAR while remaining about the same size.