HP C4096A (96A) Compatible Toner Cartridge for use with HP LaserJet 2100 and 2200 Printer Series - Black
This Amazon Imaging model AZH 96 is equivalent to  HP's model C4096A toner cartridge and works with your HP LaserJet 2100 series laser printer. Amazon Imaging asserts that its products make ideal replacements for Epson Stylus cartridges, Canon bubble jet cartridges, and many others including HP, and produces high-quality toner cartridges for today's demanding users.