This is a warranty/guarantee card that came with a Max Keilwerth-manufacturered President tenor, serial # 6046.

Although Max Keilwerth built President saxophones for Hohner in Trossingen, Germany from 1949 until his death in 1968, as this certificate shows, he also made the model/make under his Pure Tone label while still in Graslitz. (Note too, that Graslitz was still in Germany at the time.)

Unfortunately the gentleman who sent me the copy of this card didn't have the sax in his possession. It had belonged to to his grandfather, who brought both this tenor, as well as Max Keilwerth alto, home from Germany, after WWII.

Source: Martin Stuart