4 Wheel Trolley Assembly Rollers, Silent Strut Trolley, Solid Steel, M10 Bolt, Lifting Eye Nuts, 1-5/8" Wide Strut Channel (2pc). Heavy-Duty Build: Trolley assembly made with solid steel for impact resistance.Galvanized to ensure rust resistance of strut trolley.The rollers use deep groove ball bearings,work stably,Resulting in incredible strength and quality.
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