MG and MF kraft
Machine glazed (MG) bleached kraft paper
Glazed on one side against a Yankee cylinder, from bleached furnish. For food wrap, bags and print that need a white sheet.
At the mill
Bleached furnish raises brightness, and optical brighteners or filler add more. Bleaching also makes the sheet more transparent, so a brighter sheet often needs filler or weight to keep its opacity, and filler costs some strength.