Epson 4500 - Manual (Page 79)

Printing on Special Paper
8.5 mm
(0.33”) or more
3 mm
(0.12“) or more
22 mm
(0.87”) or more
CAUTION:
Envelope printing is only available at normal
temperature (41°F to 95°F or 5°C to 35°C).
To make sure that the printing fits within the printable area, always
print a test sample using a normal sheet of paper before printing on
envelopes.
Paper Handling
2-31