Vintage Shimano Ultegra FC-6500 175mm Crankset Arms 9-Speed Double Road 175 mm
Markings on arms include: Shimano Ultegra, FC-6500/6503, FC-6500, Japan VIA, Z1 175. Bottom bracket interface: Shimano Octalink splined, for compatible Octalink bottom brackets. Crank arm length: 175 mm (stamped 175 on the arms).