An 800 lb rating on a single shelf is what separates this pair from lighter wire racks. Together the two units take 4000 lbs, each frame measuring 48 inches wide, 18 inches deep and 72.5 inches tall, which is enough width for four storage totes side by side. Shelf height changes in 1-inch increments, so a bay can be sized for car batteries on the bottom and paperwork boxes up top. V-shaped mesh channels the load out to the corner posts, the reason the shelves hold that much without a wood deck. Assembly is tool-free, and the layout can be rebuilt as two half-height benches when the room changes. Each rack weighs 56 lbs, so plan on a second pair of hands for the first setup.