1.Solid wood door 2. ROTO hardware 3. Insulation glass wooden folding doorsCan be open ... .1.Advanced Germany technology, European standard notch, good hardware versatility.2. Adopting natural timber, such as larch, spruce, oak and Catalpa ... with ordinary hollow glass configuration, heat conduction coefficient is K=2.6w/(m2.k).8. All doors are openable, causing large opening area ...