Abstract: An adjustable shelving system has a plurality of generally cylindrical posts each having a plurality of vertically-spaced annular grooves therein and a plurality of tapered sleeves fitted on the posts. The tapered sleeves include an annular rib engageable with the annular grooves on the posts and an exterior mating surface. At least one plastic shelf has a plurality of tapered step holes for receiving one of the tapered sleeves fitted onto the post. The step holes are defined by an interior mating surface, and one of the exterior and interior mating surfaces is formed with a series of spaced cylindrical ledges to increase the friction between the sleeves and the step holes.

Abstract: A vertical retractable storage system includes a frame, a storage unit, and a vertical lift mechanism retractably supporting the storage unit relative to the frame. The vertical lift mechanism includes a lift structure that operates on a horizontal plane to provide both vertical and horizontal stability to the storage unit during movement between a storage position and an access position. In one aspect of the present invention, the frame is fixed to a roof or super-structure above a suspended ceiling such that in a retracted position the storage unit is disposed above the ceiling, and a base or bottom portion of the storage unit conforms with the ceiling and thereby hides the unit. In another aspect of the present invention, the vertical lift mechanism retractably supports the storage unit such that in the retracted position an access portion of the unit remains extended below the ceiling to permit access to at least a portion of the unit.