To provide equipment having the function equal to a sliding shutter or a shutter even to a completely glass-paned bay window which solves the problem that the conventional completely glass-paned bay window provides an insecure feeling from a security viewpoint because the sliding shutter or the shutter cannot be attached to it like a normal window in spite of the outward good appearance of the conventional completely glass-paned bay window.

An instrument equal to an outboard shutter is attached to the window frame to which the completely glass-paned bay window is attached. Because of this, not only crimes but also wind and rain, noise or the like can be prevented.