What are Perfect Fit Blinds? These are designed to create a flush fitting blind which looks as if it's part of the window frame. No screwing into uPVC frames, Perfect Fit blinds clip snugly in the frame of your uPVC window. The blind will actually become an integral part of the windows and doors, moving with them when they are opened or closed allowing the perfect combination of unobtrusive ventilation, shade and privacy. There is no hanging cords and you gain the window sill