The Filben record mechanism was designed and patented by William M. Filben in 1937, but was not used until the Challenger 47 in 1946 and Filben Maestro manufactured in April 1948. The Maestro sold for US$595. It is said that only 950 of this fine model were ever made, and only about 40 are thought to have survived. Right now it seems that 1100 models had been produced and at least 55 survived. Jukebox Arcade is the proud owner of one.