【Premium Durability】Crafted with aluminum alloy for excellent sweat resistance and long-lasting wear resistance, ensuring extended use in various conditions. 【Precise Sizing】Specifically designed for Kukirin G3/G4 scooters, with dimensions of 41.6mm outer diameter, 30mm inner diameter, and 6.7mm thickness for a perfect fit. 【Smooth Operation】Features dual-sided sealing that locks in lubricant, ensuring smooth steering and effortless handling during rides. 【High-Quality Construction】Offering low-noise rotation and reducing front-end squeaks for a more comfortable riding experience. 【Easy Installation】Direct replacement design simplifies the installation process, requiring no additional adjustments for a hassle-free setup. 【Enhanced Protection】Equipped with rugged rubber seals for superior dustproof and waterproof performance, extending the bearing's lifespan. Specifications: Outer Diameter: 41.6mm Inner Diameter: 30mm Thickness: 6.7mm Material: Aluminum alloy Application: for Kukirin G3/G4 scooters