A hand-held portable printer comprising: a housing having a main body and a handle extending therefrom; a rotatably driven platen roller supported in the main body of the housing; a supply roll holder that holds a supply roll of media in the main body of the housing; and a print module assembly including a printhead that selectively prints on media routed between the printhead and the platen roller from the supply roll held by the supply roll holder, said print module assembly being attached to the upper main body of the housing such that the print module assembly is movable between a closed operational position in which the printhead is proximate the platen roller and an open loading position in which the printhead is spaced apart from the platen roller, wherein the print module assembly further comprises: a printhead mounting assembly to which the printhead is mounted, characterised in that said printhead mounting assembly allows the printhead to gimbal with respect to the platen roller, and that the printhead mounting assembly comprises: a first portion upon which the printhead is mounted; a second portion by which the printhead mounting assembly is mounted to the print module assembly; and a rib extending between the first portion and the second portion of the printhead mounting assembly such that the first portion and second portion are separated by a gap therebetween. a housing having a main body and a handle extending therefrom; a rotatably driven platen roller supported in the main body of the housing; a supply roll holder that holds a supply roll of media in the main body of the housing; and a print module assembly including a printhead that selectively prints on media routed between the printhead and the platen roller from the supply roll held by the supply roll holder, said print module assembly being attached to the upper main body of the housing such that the print module assembly is movable between a closed operational position in which the printhead is proximate the platen roller and an open loading position in which the printhead is spaced apart from the platen roller, wherein the print module assembly further comprises: a printhead mounting assembly to which the printhead is mounted, characterised in that said printhead mounting assembly allows the printhead to gimbal with respect to the platen roller, and that the printhead mounting assembly comprises: a first portion upon which the printhead is mounted; a second portion by which the printhead mounting assembly is mounted to the print module assembly; and a rib extending between the first portion and the second portion of the printhead mounting assembly such that the first portion and second portion are separated by a gap therebetween. a printhead mounting assembly to which the printhead is mounted, characterised in that said printhead mounting assembly allows the printhead to gimbal with respect to the platen roller, and that the printhead mounting assembly comprises: a first portion upon which the printhead is mounted; a second portion by which the printhead mounting assembly is mounted to the print module assembly; and a rib extending between the first portion and the second portion of the printhead mounting assembly such that the first portion and second portion are separated by a gap therebetween. a first portion upon which the printhead is mounted; a second portion by which the printhead mounting assembly is mounted to the print module assembly; and a rib extending between the first portion and the second portion of the printhead mounting assembly such that the first portion and second portion are separated by a gap therebetween.