MR6706-2RS Ball Bearing Double Sealed ID 30mm OD 37mm Width 4mm SMSFC16UU this is exactly the same

this is exactly the same size as any 6201 ball bearing

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MR6706-2RS Ball Bearing Double Sealed ID 30mm OD 37mm Width 4mm SMSFC16UU this is exactly the sameMR6706 2RS Deep Groove Ball Bearing Ultra Thin Design 30mm x 37mm x 4mm Rubber Sealed The MR6706 2RS is a slim profile deep groove ball bearing designed for tight clearance applications. With dual rubber seals and just 4mm of width, it's a solid choice for high precision devices, robotics, and motor assemblies that require smooth, sealed performance without adding bulk. Pack of 1 bearing Inner diameter: 30mm (1. 181") Outer diameter: 37mm (1. 457")