The product structure is novel, according to the different needs of customers can be horizontal and vertical combination different forms of structure. Fluctuation two layer structure is same, metope and roof are not removed. Combination box adopts steel and thin wall steel plate bending a welding into standard element, its simple structure, convenient installation. Retaining Han consists of roof slab and wall panels, roof panel and wall panel are factory assembly and the main structure form the whole unit, roof panel use 0.376 mm monolayer pressure type choi steel. Spread 50 mm heat preservation cotton, 0.426 mm choi steel ceiling board, wall panel made of 50 mm double caigang sandwich plate.