Uno & Duplo: perfect simplicity and ease of use in optimal form! The Uno and Duplo folding systems are wooden based concertina walls consisting of chipboard panels joined by continuous PVC strip hinges. The hinge system allows the panels to be opened or closed in a simple operation. Both types are hung in an aluminium ceiling-mounted track. The Uno is a single-skinned folding wall, mainly intended as a visual partition. The Duplo is double-skinned and internally braced with steel hinges for greater stability. In addition, the space between the chipboard panels is filled with sound-absorbing materials to provide a higher sound insulation rating: 41 or 43dB (approx.).