Tool was formed in 1990 by Maynard James Keenan and Adam Jones. Later, they recruited Danny Carey and former bassist Paul D'Amour. They released their first demo tape in 1991 called 72826. Although demos are typically not released to the public, the band sold copies to fans. Tool released their first studio EP called "Opiate" in March 1992. After many positive reviews, they released their first full-length album, Undertow, in April 1993. In september 1995, the former basist, Paul D'Amour left the band to pursue his dreams of being a guitarists. D'Amour was quickly replaced with Justin Chancellor, which is still with the band to this day.