Abstract: A two-part binding system is disclosed, comprising an elongated sheet holder and a twin-barrel link made up of adjacent tubular portions. The sheet holder comprises an elongated planar sheet-holding section which is expandable to accommodate documents of different thicknesses. One side of the sheet-holding section terminates in a plurality of tubular barrels arranged in a spaced-apart relationship. A plurality of the links are placed in the spaces between the barrels of the sheet holders and are aligned so that a pin can pass through the barrels of both the sheet holders and the links. The links are staggered relative to each other to facilitate joining of several sheet holders in a compact, expandable book-like unit.

Abstract: A slat for a louver comprising an elongated body portion having a longitudinal axis, a front surface and a back surface, and a left edge and a right edge. The front surface has formed therein at least one channel extending substantially the entire length of the body portion parallel to the longitudinal axis, the channel in transverse cross-section being wider at the bottom than the top. The slat further comprises at least one elongated strip having a cross-section at least a portion of which is identical to the at least one channel for removable sliding engagement with the at least one channel. The color of the at least one strip is different from the color of the body portion.