This invention provides a buffering block with a Mylar bonded on the upper surface of an urethane rubber made base material on the bottom surface of the inserting port of an inserting side frame to support a toner bottle. When a toner bottle is slid and taken out from a copying machine, its inclined portion and cap portion run against the buffering block. Thus, a shock given to the toner bottle when taken out from the copying machine is eased and toner adhered around the cap portion is prevented from dropping to and contaminating the periphery of the inserting side frame.