These are the plastic based replacement nibs for the iReader X Pen Wacom EMR stylus. Since the plastic nibs wear down, due to drawing on various e-note screens, you will want to pick up this replacement series that includes 5 replacement tips.
Michael Kozlowski is the Editor in Chief of Good e-Reader. He has been writing about audiobooks and e-readers for the past ten years. His articles have been picked up by major and local news sources and websites such as the CBC, CNET, Engadget, Huffington Post and the New York Times.