With over 1,750,000 games, UltraCorr-X is the largest and most accurate correspondence chess game database ever published.
It was released only in mid-August and the slightly improved revsied version is out today. So if you buy now you will be one of the earliest adopters and have an advantage over opponents.
UltraCorr-X has been collected and edited by chess historian Tim Harding, updating his previous databases which he built up over many years while editing Chess Mail magazine.
Even if you are not a correspondence player, you need a large and up-to-date CC database to discover the latest opening ideas, tested in deep analysis by strong players working in tandem with chess computers.
Many of the authors for the Quality Chess publishing company, for example, keep a close eye on developments in master correspondence chess and quote CC games in their books.
If you are a correspondence player, you also need UltraCorr-X to find games by your upcoming opponents. You can prepare for your games by studying their opening repertoires and can use the database to find their weaknesses.
If you are interested in the history of chess, and of CC in particular, you will also find that UltraCorr-X includes thousands of games from the postal chess era which are hard to find elsewhere.