A system for mounting the front or rear sealing tape application roller of a carton or case sealing apparatus wherein the front or rear tape application roller is able to be quickly and easily replaced upon its roller shaft without the need for special tools. A spring-biased detent pin which is spring-biased between a radially outwardly position at which the detent pin so as to be engaged with and block removal of the roller from its roller shaft but which may be depressed radially inwardly so as to be disengaged from the roller and thereby permit the roller to be removed from its roller shaft.