Stephen Lee "Steve" Klein (born September 30, 1979)[1][2] is an American musician and record producer.

He is most famous for being the co-founder of Florida rock group New Found Glory, for whom he was the primary lyricist and rhythm guitarist.

Having formed New Found Glory with frontman Jordan Pundik in 1997, Klein performed on seven of the band's ten studio albums.

Klein also contributed guitar to the band's now defunct alter-ego side project, The International Superheroes of Hardcore, where he was known under the pseudonym of "Mr. Mosh".

"[3] On March 12, 2014, idobi Radio reported that on the same day New Found Glory removed Klein from the band, Klein was arraigned on multiple felony charges, including lewd acts with a minor, and possession of child pornography.