"My Size" is a song by John Entwistle. The song is the first track on his debut solo album Smash Your Head Against the Wall and ends with the main riff from one of Entwistle's popular compositions, "Boris the Spider". "My Size" was released as a promotional single in 1971. Entwistle later said: "A lot of people thought that 'My Size' from 'Smash Your Head' was actually the new Who single." The 'My Size' versions on the Sundazed and Repertoire re-releases are completely different. Both of the LPs match the Sundazed version.