The Arri M18 HMI Lamphead (120VAC) is a newly designed, more efficient lamphead built to work with a new power class of lamp--the 1800W SE HMI (not included), which has an average life of 750 hours, a luminous efficacy of 92 lumens/watt and a Color Rendering Index (CRI) greater than 90 at 6000deg.K. The M18 is an open-face, lensless fixture that combines the characteristics of a PAR and a Fresnel, creating diverging rays of light to produce a very crisp shadow. It can operate on a 20A circuit. This lamp has a beam angle (HPA) of 20deg. to 60deg., with a wide usable field angle.