Brother HL-1260 Service Manual page 275

Using Envelopes
Avoid using envelopes with the following characteristics:
• Smooth or shiny surfaces
• Protection cover at envelopes' adhesive parts
• Sealing flaps that have not been folded at purchase
• Sealing flaps as shown below
• Three or more layers of paper in the marked area
• Each side folded as shown below
Fig. 3-3 Envelope Information
CHAPTER 3 BEFORE WORKING WITH THE PRINTER
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