Maxell's penultimate and longest running lineup. Also the most sought after and beloved. Introduced about 1988. The XLII EE tape was discontinued in about 1990. Production of the UD and XLI continued until about 1998, with retail distribution ceasing about Q3 2003 after stocks were depleted. This is what I heard direct from Maxell. Because reel to reel-particularly at the consumer level, which is what these tapes were aimed squarely at, was all but defunct for most of the '90's, they sold that slowly and took that long to bleed out the excess inventory.