Shipping tray assembly for an article having casters

A shipping tray assembly for use in shipping an article having casters extending below its bottom, said tray assembly comprising a first surface, a first raised segment on said surface for supporting a first portion of the bottom of such an article, a second raised segment on said surface for supporting a second portion of the bottom of such an article, said raised segments being high enough so that when such an article is supported on them its casters are out of contact with said surface, and holding means holding said first and second segments in fixed relationship to one another, said holding means being releasable whereby said fixed relationship can be changed, said holding means upon being released enabling said second raised segment to be removed from said tray assembly thereby providing an opening in said assembly whereby an article with casters extending below its bottom and located inside said tray assembly can have its casters lowered onto said surface and can be rolled out of said assembly through said opening.