Genuine OEM Lexmark MS310 D Toners
Black toner and the imaging unit are separate 50F supplies in the Lexmark MS310d. The printer also uses a distinct fuser and redrive assembly for maintenance, and those parts solve different problems from low toner.
Toner Buzz carries genuine Lexmark 50F toner and imaging units for the MS310d, along with fuser and redrive components. Use the part named in the printer's notice to distinguish routine toner from an imaging or redrive service need.