Upgrade your bicycle's performance with these premium ABEC-7 rated ball bearings. Measuring 17x30x7mm, these high-precision bearings feature a distinctive blue sealed design that delivers exceptional smoothness and reliability. The double rubber seals (2RS) provide superior protection against dust, dirt, and moisture, ensuring consistent performance in various riding conditions. Each pack includes 4 bearings, perfect for both front and rear wheel hub applications. These bearings are engineered for minimal friction and low noise operation, contributing to a more enjoyable riding experience. The high-grade construction maintains tight tolerances for optimal rotational stability, while the precision engineering ensures consistent performance at higher speeds. Whether you're upgrading your current bearings or replacing worn ones, these robust components offer the perfect blend of durability and smooth operation for your bicycle wheels.