1200-watt equivalent veg/bloom full spectrum led plant grow light fixture with g rectangle vents use high density window screen 20 in. We do not accept P. Long, made from high quality aluminum, not only does the duct act as in intake and exhaust piping for active-cooled fixtures and reflectors, but also stores and dissipates heat at a steady rate, reducing room temperature fluctuations, 3-ply ultra-thick construction for durability.