These phonebook-sized, B&W, value-priced collections contain about 25 issues each of consecutive continuity; picking up from the X-Men's "relaunch" in 1975's "Giant-Sized X-Men #1".
With more volumes under its belt and starting from a later point in time than most any other marvel title receiving the "essential" treatment, this Marvel Essentials series reprints more recent works than any other title in the line except for "Wolverine".
— Description from Comic Vine community (comicvine.gamespot.com · https://comicvine.gamespot.com/essential-x-men/4050-21196/).
