Features：1. The portable size makes it easy to carry along.2. The retractable spring could do a great job.3. This ball shape spring lock comes with delicate workmanship.4. Made of ABS, it is sturdy and durable5. A good accessory for indoor cycling bikes.Specification：Material: Steel and ABSColor: BlackScrew Diameter: M18 x 1.5Screw Length: 20mm/0.79"Shaft Length: 11mm/0.43"Total Length:65mm/2.56“Shaft Diameter: 10mm/0.39"Max Diameter: 54mm/2.13"Package Included:2pcs x Pull Pin Spring Knob.
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