I found this while surfing. I donít know if this is common knowledge, but it is very useful info. I also donít know if this is particular to the Elo screens (such as the eBay Kiosk).

ē If you plan to seal your front bezel around the viewing/display area, be sure to use the Elo Volara foam, or an equivalent closed-cell and non-gas/chemical-emitting type of foam (available from DFI and other suppliers). Volara is an Elo trademark.
ē This foam typically must not be wider than a quarter inch (less foam pressing on the surface-wave sensors at the edge of the glass), and the thickness of this foam can be 1/16" or 1/8".
ē The adhesive side of the foam must stick to your bezel, and not the touchscreen/glass.
ē Do not use a generic-type or automotive-type foam which may cause the touchscreen not to properly work -- the touch points may be totally out of calibration and cannot be recalibrated, or there will be dead zones where the touchscreen does not work, or the entire touchscreen simply will not work at all. (To debug, just loosen or remove your bezel and re-test the touchscreen functions.)

I found the information on the following page: http://dfiusa.com/p_m_download/index.html

There are some other useful touch screen tips on the page, such as what to use to calibrate your screen.