This magnet commemorates Elvis Costello's infamous December 1977 Saturday Night Live appearance as a last minute replacement for the Sex Pistols. He absolutely stopped a live network show on air to play a song the staff had never heard, "Radio Radio". Here he is stopping the band after a bar of the rehearsed song. "Ladies and gentlemen, there's no reason to play that song here tonight."
He sabotaged them with this song attacking the commercial radio industry because he assumed the evil corporate NBC/GE wizrds would never let him speak such truth to power on their own airwaves - as if they knew or give a flying fig about some punk rocker's protest song. So he went rogue. This silly and childish gesture is one of the very top memorable and archetypal moments of Elvis Costello's distinguished career.