Miniature Metric Series, Single Row Deep Groove Bearing, Open - (4 x 9 x 4 mm)

684 is a 680 miniature series open single row deep groove radial ball bearing with a 4 mm bore, 9 mm outside diameter, and 4 mm width. Built with a thin-section miniature profile, precision-ground raceways, and steel balls for smooth rotation in compact shaft assemblies. The open construction allows direct lubrication access and is best suited for protected housings or small mechanisms with planned lubrication. Commonly used in small motors, RC equipment, model assemblies, compact robotics, and precision mechanisms. Product Specifications: Bearing Type: Open Single Row Deep Groove Radial Ball Bearing Part Number: 684 Series: 680 Miniature Series Inner Diameter (ID): 4 mm Outer Diameter (OD): 9 mm Width (W): 4 mm Closure Type: Open Load Direction: Radial and Light Axial Loads Precision Rating: ABEC 1 Material: Chrome Steel Lubrication: Requires Application Lubrication Applications: Small motors RC equipment Model assemblies Compact robotics Precision mechanisms