A precision-cut, 960mm long, and 100mm wide, straight reversible wood panel has been prepared from flexible aluminum sheet with a 45-degree slope on the top, and a 7.0mm radius for the upper corners. The surface protects from moisture. The straight reversible wood panel is coated with an alder-type primrose yellow wood primer pigment. It is assembled with plastic hinges and six concrete counterweights. The set includes a straight reversible wood panel and the corresponding number of hinges.)