Abstract: A connection system is disclosed for securing tubular truss members together in a manner that keeps the attachment connectors internal and out of sight. The connection comprises tubular truss members with diametric opposite countersunk holes sized to accept flush nut inserts, screws, and a core connector that is sized to be intermediate to the tubular truss members. The core connector provides anti-rotation of flush nut inserts, while screws and flush nuts are tightened to secure connection.