Five tiers on a swivel base means a whole collection stays reachable from one spot - turn the column rather than walking around it. The shelves fold flat when the unit is not in use, which no fixed bookcase offers. PP and ABS keep the weight to 16.5 lbs at 68.5 in tall, with each shelf rated to 22 lbs. The footprint is only 14.5 x 14 in. Translucent panels let the shape of what is stored show through. Assembly is required; one bookshelf and an instruction sheet ship per carton.