Extreme is an American hard rock/funk metal band formed in Boston, Massachusetts in 1985, fronted by Gary Cherone and guitarist Nuno Bettencourt. They reached mainstream success with the 1990 album ‘Pornograffitti,’ which featured the chart-topping acoustic ballad ‘More Than Words.’

Extreme sold over 10 million albums worldwide and were among the most successful rock acts of the early 1990s; ‘More Than Words,’ an acoustic guitar duet, remains a widely covered and studied piece among guitarists.

Sources:

• https://en.wikipedia.org/wiki/Extreme_(band)