a hand - held cutting tool which is composed of a housing defining a bottom to rest upon a surface and includes within the housing a blade cartridge secured therein on which there are a plurality of blades swingable so that the cutting edge of each blade is exposed or retracted so that the blade is completely within the housing , the blades are rotated between the two positions defined above by means of spacer means which include an operating surface preferably exteriorly accessible on the housing .