hollow rectangular pier 箱型桥墩

hollow rectangular waveguide 矩形空心波导

rectangular hollow tube with opening 开孔方管

rectangular hollow 中空矩形

rectangular hollow block 矩形空心块

rectangular hollow piers 矩形空心墩

rectangular hollow conductor 矩形空心导线

rectangular hollow conductors 矩形空心导线

rectangular hollow bridge pier 矩形空心桥墩