Abstract: An wc-disposable ostomy bag has a pouch of alkali-disposable material and an adhesive flange in two parts. One part is an inner ring permanently bonded with the pouch around its opening. The other part forms the major part of the flange and is an outer ring attached with the pouch by a temporary, manually-separable bond. The outer ring can be disposed of separately from the pouch and inner ring, which are placed in a wc to which an alkali has been added. The small size of the inner ring enables it to be flushed away.