The finest quality printers only perform at their best with the right toner. The Lexmark T series print cartridges are specifically designed to assure optimal print quality, with crisp, dark output from first print to last. The Lexmark T520, T522 print cartridges are designed to work with T520, T522 printers and will not work with other products. Average Cartridge Yield 20,000 standard pages. Declared yield value in accordance with ISO/IEC 19752.