Decorative M-21 Modern Package of 4 Crown Molding Styrofoam.52"x2.1/4"x2.1/4" Styrofoam molding M-21 are convenient and easy to install. They are easily placed on the inside corner of two attached walls. Save money do it your self!Affordable,green,eco-friendly,remodeling,renovation. Kitchen remodeling,decorative plain crown moldings attached to plain outside corners allready factory prepare!