A pen-type computer peripheral device includes an elongated housing containing a PCBA having a plug connector, and cap/cover that is slidably connected to a front portion of the housing. Locking structures are respectively integrally molded onto opposing surfaces of the housing and cap/cover that cooperate to prevent separation of the cap/cover from the housing. By manually pushing (sliding) the cap/cover relative to the housing, the plug connector is effectively moved between a retracted position, in which the plug connector is disposed inside the cap/cover, and a deployed position in which the plug connector extends through a front housing opening of the cap/cover such that the plug connector is operably exposed for insertion into a host system.