California Light Works CLW0400 Solarstorm 880W LED with UVB 176 super high Flux us made 5 watt LED emitter diodes Built-in 2 x 15 watt uv-b T8 tubes with a separate switch Uniform 90 Degree jewel quality glass primary optics, no secondary optics Uniform, 4' x 4' core coverage area, no wasted light High photo-synthetic photon Flux (PPF) to penetrate canopy and deliver unparalleled yield results