The 10PCS MR128ZZ P5 8x12x3.5 Single Row Deep Groove Ball Bearings Double Shielded offer a compact, precision bearing solution for small machinery and hobby projects. With a 8x12x3.5 mm size, P5 precision rating, and double shielding, these bearings are designed to deliver reliable performance in tight spaces while protecting against dust and debris. Key benefits precision in a small package: P5 tolerance delivers smoother operation on miniature shafts and speed applications. Durable, lowmaintenance protection: Double shields (ZZ) help retain lubricant and keep contaminants out, extending bearing life in challenging environments. Consistent performance in tight spaces: Single row deep groove design supports radial loads with good axial guidance, ideal for compact assemblies. Easy replacement and standard sizing: 8 mm bore, 12 mm outer diameter, and 3.5 mm width match common micromechanical configurations. Key attributes Model: MR128ZZ Precision: P5 Type: Single Row Deep Groove Ball Bearing Shielding: Double Shielded (ZZ) Size: 8x12x3.5 mm (inner diameter 8 mm, outer diameter 12 mm, width 3.5 mm) Quantity: 10 bearings per package Compatibility: Suitable for shafts with an 8 mm bore Material: Not specified in the listing Specifications at a glance Inner diameter: 8 mm Outer diameter: 12 mm Width: 3.5 mm Configuration: Single row deep groove ball bearing Shields: Double (ZZ) Precision: P5 Package: 10 pieces What makes it unique Combines a compact 8x12x3.5 mm footprint with precision P5 tolerance, enabling precise motion in smallscale devices. Double shielding provides robust protection against dust and grime, reducing maintenance and downtime in demanding environments. The MR128ZZ designation identifies a standard, widely compatible bearing format suitable for a range of compact applications. Applications and use cases Small electric motors and gearboxes: replacements in hobbyist drones, RC cars, and micromotors where an 8 mm bore is required. 3D printer components and CNC prototypes: bearings for compact linear axes, idler pulleys, and extruder assemblies with limited space. Robotics and automation projects: hobby robotics, small actuator shafts, and precision positioning mechanisms needing reliable, lowfriction rotation. Installation and handling notes Ensure the shaft diameter is precisely 8 mm and the housing accommodates a 12 mm outer diameter bearing. Clean mounting surfaces and use appropriate press or bearing installation tools to avoid damage. Orient the shields so they face outward to maximize protection against contaminants where needed in the assembly. Apply compatible lubrication if your application requires periodic maintenance beyond shielded protection. Package contents 10 MR128ZZ bearings with double shields, ready for swapin replacement in compatible assemblies. This description reflects the product's brand, specifications, model, and features: MR128ZZ, P5 precision, 8x12x3.5 mm, single row deep groove ball bearings, double shielded, 10 pieces. It presents clear benefits, key attributes, compatible use cases, and practical guidance to help informed and straightforward installation.