To prevent intrusion of rain water into a fire extinguisher storage box by eliminating a clearance formed in a top plate when the top plate is manufactured by bending.

Respective suspension parts 4a, 4b, 4c and 4d suspended to the front/rear/left/right respective sides of the top plate 4 and the top plate 4 are connected via arc plate parts 41, 42, 43 and 44 respectively to be integrally formed. The adjoining suspension parts out of the respective suspension parts 4a, 4b, 4c and 4d are continued and integrally formed via the respective arc plate parts 46, 47, 48 and 49. The suspension parts, the top plate 4 and the arc plate parts collected in respective top parts 11, 12, 13 and 14 are continued and integrally formed via partial spherical shells.