Welcome to the Brother MFC-3100 product page. Here you can find information and pricing for your Brother LC21M Genuine Brother Ink Cartridge. Easy online ordering of your LC21C Genuine Brother Ink Cartridge, LC21BK, LC21Y, LC21M, can be completed from this page. Tonerprice.com backs all of our cartridges with our exclusive warranty. As always, we provide free ground shipping on orders over $75 within the contiguous United States from 5 warehouses nationwide.