Elevate your bicycle's performance with these premium 6903-2RS bearings featuring hybrid construction that combines stainless steel races with ceramic balls. These precision bearings are engineered to ABEC-3 specifications, delivering consistent and smooth rotation while minimizing friction. With dimensions of 17x30x7mm, they're perfectly sized for both front and rear bicycle hub applications. The double rubber seal (2RS) design provides superior protection against dust and moisture intrusion, while the stainless steel construction offers excellent corrosion resistance for lasting durability. These bearings are manufactured to exacting standards, ensuring reliable performance in various riding conditions. The ceramic ball design helps reduce rolling resistance and operating temperatures compared to traditional all-steel bearings. Whether you're upgrading your current bike's bearings or building a custom wheel set, these bearings deliver the precision and durability needed for optimal wheel performance.