The Dalite 36980L Advantage Electrol Projection Screen is a unique design. Construction of this ceiling recessed screen permits the case to be installed first and the fabric added later once a suitable projection surface is decided on. This is a big "plus" since companies constructing viewing rooms may not be certain of what they need in a screen. However, the Advantage permits the basic frame to be installed in the ceiling - ready for a finished fabric assembly to be added when all is prepped. The exceptionally quiet motor gives it an edge over similarly priced screens. Quiet "up" and "down" operation makes the Advantage more professional in appearance as well as less distracting to your audience.