  With future experiments proposing detectors that utilize very large-area GEM
foils, there is a need for commercially available GEM foils. Double-mask
etching techniques pose a clear limitation in the maximum size of GEM foils. In
contrast, single-mask techniques developed at CERN would allow one to overcome
those limitations. However with interest in GEM foils increasing and CERN being
the only main distributor, keeping up with the demand for GEM foils will be
difficult. Thus the commercialization of GEMs has been established by Tech-Etch
of Plymouth, MA, USA using single-mask techniques.
  We report on the electrical and geometrical properties, along with the inner
and outer hole diameter size uniformity of 10 $\times$ 10 cm$^2$ and
40$\times$40 cm$^2$ GEM foils. The Tech-Etch foils were found to have excellent
electrical properties. The measured mean optical properties were found to
reflect the desired parameters and are consistent with those measured in
double-mask GEM foils, and show good hole diameter uniformity over the active
area. These foils are well suited for future applications in nuclear and
particle physics where tracking devices are needed.
