CPG International is a parent company of AZEK Building Products, No. 1 in premium decking and a leading manufacturer of high performance, low-maintenance outdoor building materials under the AZEK® and TimberTech® brands, announced today an agreement to acquire WES, LLC. A leader in the aluminum railing industry, WES, LLC sells engineered railing systems and assembly machines under UltraLox, Harmony and other brands. The transaction is expected to close before Dec. 31, 2017.