Related Clues:

• Part of a 45
• Less-played 45 part
• Improbable hit
• Half an audio cassette
• Hit, on a 45
• Less popular song on a single, usually
• Back of a hit single
• Flip of the flip?
• Less promising of two songs
• Lesser-played half of a 45
• 45's back
• LP surface
• It's usually not a hit
• Less popular song, often
• Single surface