Other than the commonly used Xerox toner cartridges, imaging drum units (like the 101R00555) are the most well-known consumables in laser printers. Designed to handle the black powder that comes from the Xerox toner cartridge, this genuine 101R00555 image drum plays an incredibly important part in the printing process.Drum units play such an important role, that original Xerox components are always preferable if you can justify one. This genuine 101R00555 black imaging drum unit is guaranteed to be compatible with the Xerox Phaser 3330 and all other printers found listed on this page.