Ceramic Metal Halide (CMH) grow lights were first developed in the late '60s and are now interchangeably termed Light Emitting Ceramic (LEC) as both refer to the same technology.  CMH grow lights have a wide and consistent spectrum that produce powerful light output that contains UV just like the sun.  This gives plants their best growth potential.  The difference between a CMH lamp and MH lamp is the ceramic emitter component.  It is this ceramic tube that enables the ceramic metal halide grow light to withstand much higher temperatures.

315W / 630W CMH Footprint Coverage

CMH lamps are reccommended for universal positioning (vertically and horizontally above the canopy) without causing any damage to the bulb.  The light distribution is so intense, the footprint coverage is larger than what MH and HPS bulbs provide.  With this intensity comes heat requiring the 315W CMH light to be hung at a distance of 2ft from the canopy, and the 630W CMH hung at least 3ft distance from the canopy to cancel out the effects of the heat. The 315W CMH lamp ranges in coverage 3ft x 3ft  -  4ft x 4ft.  The 630W CMH lamp coverage ranges from 5ft x 5ft  -  6ft x 6ft.