... match a corner2. promptly delivery4. offer skills for gypsum manufactory5. various sizeB features and advantages( specific description). ... proof, sound & heat insulated.We select the A-class gypsum powder (mineral purity =93-95%, crystal water T =18%, ... & Wide Selections.Our main products are gypsum one-piece art ceiling , gypsum cornice, gypsum ceiling corner, decorative sideline, chair rail, ...