Used to keep acrylic paints moist, these sponges are used with Masterson's Sta-Wet Premier Palette to keep your water-based paints stored and wet until you're ready to use them again. Details: Yellow cellulose sponge12" x 16" (30.5cm x 41cm)Long-lasting and highly absorbentFor use with the Masterson Sta-Wet Premier Palette (sold separately)