CEMCO’s Double “J” (XJ-15) Control Joint relieves stresses and strains in large plaster walls and ceilings. This product has expanded flanges for proper keying and easy application. Its unique design permits the plaster to key underneath the rolled edges for added adhesion while the walls expand and contract under typical conditions. The pull tape on the joint itself provides a clean finish when removed after the finish coat. Double “J” Control Joint is fabricated from 26 gauge galvanized steel in standard G60 coating. G90 coating is available upon request.