The product code C13T845198 (also known as the T8451 or T8451 Black) is a specific Black Ink Supply Unit (ISU) designed for certain high-capacity, high-speed Epson WorkForce Pro printers.
 
Pigment-Based Ink (Epson DURABrite Ultra or similar technology)
750 mL (This is a very large volume, designed for extended use.)
Extremely high, often rated for approximately 75,000 pages (in conjunction with the color ISUs, yield is typically shared across a long period).