Epson’s high speed industrial full color label printer.
Due to the high speeds of the printer, 2 types have been released. Epson ColorWorks TM-C7500G (glossy)  and the Epson ColorWorks TM-C7500 (matte and BS5609).

The Epson ColorWorks C7500 (without “G”, or NON-G as Epson calls it) does not allow glossy media to be processed.
There are some exceptions but the basic rule is that you have to use the Epson ColorWorks C7500G (with the “G”) for glossy media. The only difference is in the inks that are used in the printer, other than the inks there is no real hardware difference.

The Epson ColorWorks C7500 has a brighter and wider color output, deeper colors, better blacking and the inks are resistant to chemicals and many other influences.

The Epson ColorWorks C7500G inks are adjusted to glossy media by making the drying speed even quicker, than results in a ink that drys quick enough to print even glossy media at tremandous speeds up to 300 mm per second. Therefore the Epson ColorWorks can be used on more materials than the Epson ColorWorks C7500 (Without “G”) can. The downside is the lower color spectrum that these inks have and the lower resistance to influences like UV-light and chemicals.