Yes, the Canon MAXIFY GX6550 printer is capable of printing C5 envelopes. The printer supports various envelope sizes, including DL, COM10, C5, and Monarch.

Yes, you can scan double-sided documents with the Canon MAXIFY GX6550. The device has a front-accessible automatic duplex document feeder (ADF) for up to 35 sheets, which allows both sides of documents to be scanned automatically.

Yes

In fact, the description seems to be wrong, the information should be stored in the specifications. Thank you for pointing this out.