Four-head grow lights are the reason this stand works in a room with no south-facing window - 10 brightness levels and auto timers at 3, 9 or 12 hours mean the plants get a full day regardless of the weather outside. The line runs 118 in. Eight tiers rise to 62 in on a 26.5 x 12 in corner footprint, with large shelves of 24 x 12 in and small ones at 8 in square, each rated 10 lbs. Metal and engineered board weigh 17.5 lbs per stand, 35 lbs for the pair. Assembly is required.