Part works series of graphic novels featuring Marvel characters published by Hachette Partworks Limited in the U.K. Originally intended to be 120 parts (including the 'classic' issues) ending mid 2016. This was extended a number of times since, with the collection finally finishing with 280 parts.
Each issue has two numbers; an issue number as a sticker on the cover, and a number on the spine giving the order they should be shelved in order to show a panoramic picture across the spines. The classic series sits to the left of this series.
Volumes 1 - 80 have ISBN's. From volume 81 onward there is no ISBN printed, instead they are grouped under ISSN 2048-6774.
Hachette Partworks now refers to this series as the 'Marvel Ultimate Graphic Novel Collection (2012)'. This is because in 2016 Hachette Partworks re-launched the series with the same books but with different volume numbers on the spines, this newer series is referred to as the 'Marvel Ultimate Graphic Novel Collection (2016)' and ran approximately 110 issues behind this one.
Although it is easy to confuse books between the two series, the easiest way to distinguish between them is by the four characters at the top of each front cover. From left to right this series has Wolverine, Storm, Spider-Man and Hulk.