From the manufacturer:
An all-purpose canvas, Classic Cotton Stretched Canvas is great for traditional painting techniques as well as mixed media, aerosol art, home decor and craft project and is suitable for use with all acrylic paints, oil paints and other wet or dry media. The unbleached 5 oz. cotton duck is primed with acid-free acrylic titanium gesso to a finished weight of 10 oz. and stretched around and back-stapled to kiln-dried solid pine stretcher bars. Sizes with a dimension of 24" or longer are braced for additional support.