Similar to the F2, the sliding door F3 system comprises of independent, but framed double glass panels. F3 is as flexible and versatile as the F2, but it is designed to bear thicker tempered double glass for additional insulation and robustness against more challenging environments. Αny number of framed glass panels can be used, any of them can be relocated individually and parked to a remote storage space. It is ideal for large openings where additional robustness and security may be an issue, such as shop fronts and exposed spaces that need to be secured (e.g. balconies). The panels, which are suspended and move along a rail, employ heavy type rollers which enable smooth, unflappable motion and stability in spite of the considerable weight of each panel. No additional floor railing is used, while panels are secured to a standstill with locks or floor latches. Sealing between doors is achieved with specialized rubber stripes, while sealing between the doors and the wall is achieved with brushes. Top and bottom aluminum profiles are equipped with 18mm insulating brushes in order to seal off minor gaps and maximize insulation and watertightness. Door sizes vary, ranging up to 120cm in width and 300cm in height. The F3 system employs double crystal glass to ensure good insulation; it can be tempered or laminated, and up to 23mm in thickness. The opening door is provided with or without a floor spring mechanism, and any intermediate panel can be transformed into an opening door upon request, with the addition of the corresponding ceiling mechanism. These doors can be a single-wing panel, as well as double-wing panels.