A mega stadium-convention center complex is disclosed comprising an impressive pyramid building with a 670-foot pinnacle and a base covering more than 20 acres. Upper and lower X-axis guides are attached to the upper and lower portion of front surface of the column, which is mounted on the bed in the vertical direction, in the horizontal direction. Low load and high load modes are distinguished by the combustion characteristics of an amount of fumigated fuel added to the combustion chamber. The clamp unit removably clamps at least one of the lace units, and includes at least one flexible string section, and at least one clamp member.