This 11” cardboard tube let fans “hum along” to their favorite tunes through a colored flared mouthpiece (red, the rarest of four colors). Manufactured by Louis F. Dow under an NEMS license, the idea actually came from Merrimaker Corp., which traded away broad U.S. rights in exchange for exclusive resale privileges — a deal that later spun off a “Beatles Paper Hat” promo for a Chicago soft-drink bottler.