I forgot about this item. Once again, bought at a car boot for a ridiculous price (about £3 if i remember correctly) but it has no date markings or stamps that i can see. The only markings are ....
1. A stamp just below the neck thread which reads ICO'55/56
2. Stamp on both brass press studs which reads 'knip hier'
Anyone any idea of the era ? The colour of the canvas is faded blue so not sure if it is even American !