Amazon.com: E-Z Ink (TM Remanufactured Ink Cartridge Replacement for Epson 410XL 410 XL T410XL to use with Expression XP-640 XP-830 XP-7100 XP-530 XP-630 XP-635 (2 Black with The Newest Updated Chip) :
Epson Expression Premium XP-640 Review | Tested by GearLab
How to replace Epson XP 640 ink, manually or with the on screen assist. - YouTube
Epson Expression Premium XP-640 | Take the Tour of the Small-in-One Printer - YouTube
How to Print on Multiple Envelopes (Epson XP-900, XP-640, XP-645, XP -630/635,XP-620/625) NPD5341 - YouTube