Patent ID: 8109316

Claim:
A slat member ( 100 ), with a top end configuration and a bottom end configuration formed by bending a top portion and bottom portion of an elongated sheet respectively, the slat member ( 100 ) comprising: an upper shoulder ( 101 ) and a recess 102 , formed on the top end of the slat member ( 100 ), the recess ( 102 ) being formed on one side of the upper shoulder ( 101 ) and lower than the upper shoulder ( 101 ); an upper hinge part ( 103 ), extending upward from the recess ( 102 ) a first predetermined distance and bent toward the upper shoulder ( 101 ) to shape a first hook; a lower shoulder ( 104 ), formed on the bottom end of the slat member ( 100 ) corresponding to the upper shoulder ( 101 ); and a lower hinge part ( 105 ), extending downward from the lower shoulder ( 104 ) a second predetermined distance shorter than the first predetermined distance and bent toward a direction away from the lower shoulder 104 to shape a second hook.