Epson Stylus 1520 User Manual page 152

You can load up to 10 envelopes in the sheet feeder. Make
sure the printable surface is face down and the flap edge
loads first.
When loading C5 envelopes, remove the rear edge guide and
re-install it to match the length of the envelopes as shown
below.
.
When you load envelopes into the manual feed slot,
position the right edge guide so that its right edge is even
with the arrow mark on top of the manual feed guide. Load
envelopes printable side up. See "Loading paper manually"
earlier in this chapter.
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Paper Handling