Yamaha PSR-540 Keyboard Floppy Disks Also compatible with Yamaha PSR 7000, PSR 8000, PSR 9000 & 9000 Pro, PSR 340, PSR 350, PSR 540, PSR 550, PSR 450, PSR 630/730, PSR 640/740, PSR 1000/2000, PSR 1100/2100, Tyros1
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