MacLellan Concrete Co Inc., 650 Peverly Hill Rd, Portsmouth, NH 03801, US

National Gypsum Company, also known as NGC, is a manufacturer of building products. It is one of the leading, private gypsum board producers in the world. The company offers a line of interior finishing products, such as joint compounds, tapes and textures. National Gypsum Company operates laboratories, mines, paper mills, cement board plants and sales offices. Founded in 1993, the company manages a technology innovation center in Tennessee. It offers gypsum boards, rock, crushes and grinds. The company provides products under the XP, Hi-Abuse XP, Hi-Impact XP, PermaBase and e2XP brands. It operates one of the largest gypsum quarries in Nova Scotia in Canada. National Gypsum Company manages plants in Florida and Pennsylvania. The company manages National Gypsum Properties.