PURPOSE: To simplify assembly by providing grooves for end coupling to form slots there-through a curtain sheet passes at a pair of legs elastically deformable.

CONSTITUTION: Grooves 4 for end coupling are provided to form slots there- through a curtain sheet passes at a pair of legs 2 elastically deformable, and the legs 2 are coupled together at the bottom center 3 so that a casing 1 is formed. The legs 2 are deformed so as to be identical to the contour having an auxiliary recess 11 of a side supporting constituent element 10, and the casing 1 is attached to the constituent element 10. In the groove 4 in the casing 1, the end of a panel member 6 is engaged, and supported thereby.