1. To reinforce the rigidity of the upper rim, the C chanel is fixed by spot welding along the rim, and the ends of each chanel are connected by a safety cap
2. Both side plates have a curved shape that can be collected and poured out when pouring grains (rice) stored therein by forming a curved shape outward
3. To reinforce the forklift insertion part, a reinforcing plate for rigidity reinforcement is spot welded to the inner surface