PURPOSE: To easily assemble and disassemble by outwardly inclining four plate sections forming a square case from a front edge section for an inserting side to a square hole of a base plate, by resiliently contacting to an inner surface of the square hole, and by putting the base plate between a nail provided at a plate section and a stopper.

CONSTITUTION: Stoppers 16 are formed cutting and uprighted on four plate sections 12 to 15 forming a square-case-shaped metal article 11, an tapered nails 19 projecting outward are formed cutting and uprighted. Edge section for an inserting side to a base plate are connected to each other at a plate section 21 surrounding square hole 20. Projections 22 and projections 23 bending downward are further provided to each plate sections 12, 13. The four plate sections 12 to 15 are inclined outward from the plate section 21. The four plate sections 12 to 15 are resiliently contacted to the inner surfaces of the base plate thereby, and the base plate is put between the stopper 16 and the nails 19 to make it easy and firmly to be assembled and disassembled.