Jason "Cone" McCaslin is a Canadian musician, singer, songwriter, and record producer, serving as the bassist and backing vocalist of the band Sum 41. He and frontman Deryck Whibley are the only two members of the band to appear on every studio album.

Sum 41 is a Canadian rock band from Ajax, Ontario. The band was formed in 1996 and currently consists of Deryck Whibley, Dave Baksh, Jason McCaslin, Tom Thacker, and Frank Zummo.