Abstract: A non-electric plug to be removably located in the output jack of a portable, hand-held electronic device to prevent moisture, dust, and other foreign matter from entering the jack when an electrical connector has been detached from the jack. According to a preferred embodiment, the electronic device is a mobile cellular telephone (e.g., that known commercially as an iPhone) and the output jack thereof is a headphone jack. The plug includes a cylindrical body and a relatively narrow pointed tip to be received inwardly of the output jack. A relatively wide blocking head extends across the plug body so as to lie flush against and in direct contact with the exterior of the electronic device. A handle stands outwardly from the blocking head to be grasped by the fingers of a user at which to receive a pushing or pulling force to be applied to the plug body. One end of the flexible attachment is tied to the plug at the handle so that the electronic device can be carried and suspended from the attachment.