CGC Synko® Classic Finish® Compound (Mud) Coverage: For joint finishing, the 17 L box covers approx. 450 ft.2 (42 m2) of gypsum panels. Application: The fill (2nd coat) and finish (3rd coat) coats in drywall finishing. Synko® Classic Finish® Compound (Mud) is easy to apply and provides a smoother finish. While Classic Finish® should not be used to affix paper tape or non paper-faced metal corner bead, it can be used for all 3 coats on paper-faced metal corner bead. Data Sheet