Cuerpo de cámara fotográfica Zenit TTL USSR SLR con estuche de cuero, falla de cortina por favor leer

The case is a little worn and scuffed in places but is perfectly useable as-is. Everything works except the shutter curtain sticks which appears to be due to a broken or loose curtain ribbon. When pressing the film advance or the shutter release button the curtain tries to move but does not slide smoothly.

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