With El Dorado two-piece slip frames, any existing rough opening can be wrapped with a lead line welded window frame that is very close in appearance to a borrowed light frame. Frames are made standard with a single rabbet (double rabbet shown in isometric drawing) and removable stop and, unlike typical telescoping view frames, are available with mullions. Frames are ordered from El Dorado using actual glass size. To calculate the rough opening necessary from the actual glass size, add 1 3/4” to the width and 3/4” to the height of the glass. To calculate the overall frame dimensions from the actual glass size, add 4 1/4” to the width and 4 1/4” to the height of the glass.