Vein is the thirteenth album by Japanese experimental band Boris. The album was released on vinyl on October 2006 through Important Records and was limited to 1500 copies only. Vein became somewhat controversial for the long delays prior to the release but most importantly for presenting two different albums under the album's title. As the label in charge of the release explained, "Every aspect of this beautiful release was planned and designed by Boris and they have stated that it has very special meaning for them".

In 2013, the band announced that the album would be released as a 2-CD set but that this was not a reissue of the album, but rather a re-arrangement of both albums combined. The label in charge of this release explained that this release sounds different from the previous versions. The album was packaged in two 3" CDs with the same printed outer edge as the vinyl release to make them appear to be traditional 5" CDs.

Part of track A7 of the hardcore vinyl version is used in the untitled final track of Smile. It is present unadulterated, but as an alternate, bass-heavy mix, on the Southern Lord US vinyl pressing of Smile as "VEIN;" it is thus removed from the untitled song. The 2013 CD pressing of Vein moves this to track 11 and is yet another mix, this one even incorporating the backwards guitar melody from the untitled Smile track. This creates a circle of sampling that intermingles the two albums.

On November 2004, first hints of the album were given by the label Important Records who, in a newsletter, informed that the band had just completed the recording of the then untitled album and more information was going to be released in the future. However, for more than a year, no information about the release was given until May 2006 when the label finally revealed concrete information about the album including the picture around the edges of the vinyl, the title, and estimated date of the release:

Since we're getting lots of emails about this I figured it was probably time to give everyone someinsight into what we're doing. The vinyl only Boris release "Vein" should be available in the next 30-60 days. It's been an extremely challenging and time consuming process. There's been a couple of months of daily communication with the pressing plant and more trouble shooting than I have the space to elaborate on.

The label expressed some frustration with the many details involving this release, in particular, the vinyl itself. The label explained that in order to obtain the finished product they had to use a screen printed image on clear mylar in order to give the impression of clear vinyl with an image suspended within it. Additionally, the label expressed how even making the stickers for the album have been a challenge as they were designed on a custom size and require hand building a die to cut them. First attempts at this were unsuccessful with the image smudging when the vinyl was pressed over it.

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Wikipedia