Mudmasky Serum-Infused Eye Mask Full size. 30ml/1.0 fl oz. New. Never used. Sealed. Retail: $57 The Serum-infused Eye Mask is specially formulated for the thin and sensitive skin under your eyes. This concentrated mask contains a super-high level of natural antioxidants. It improves the elasticity under your eyes after 4-7 uses. As an effect, the skin under your eyes looks visibly less dark and less sunken.