The success of the book The Josh White Guitar Method [1956] prompted Mairants to commission a Zenith “Josh White” signature guitar based on Josh's Martin 0021 from German guitar maker Oscar Teller. ... On the last page of "Josh White Guitar Method" (printed 1956) there is a photo of this Zenith Josh White signature guitar and some text about it.^[1] ... Mairants also commissioned German guitar manufacturer Framus to make further Zenith Guitars, with Boosey & Hawkes being the sole distributor and each one personally signed by him. These included the Zenith Model 17 acoustic which became Paul McCartney's first guitar and on which he subsequently wrote most of his early songs.

— English Wikipedia "Ivor Mairants#Biography"

In the 50s Paul McCartney owned a model of a Framus Ivor Mairants "Zenith" guitar. He had originally been given a trumpet for his 14th birthday in 1956 but he learned he could not possibly sing playing a trumpet so he swapped it for a Framus "Zenith" model 17. He used it to compose some of his first songs with it including "When I'm Sixty-Four". It still hangs in his studio.

— English Wikipedia "Framus#Progress"