Accessories:BRAKE DISK-2PCSM4x2.5x15 Screw Pin-2PCSOriginal Name / Part No:AR310447Product major functions & usage:Connecting the CVD to the wheels in order to transfer the power and lead a smooth drive.Major advantages of upgrading to this part/product :1. MODERN METALLIC DESIGN WITH SWIRL ENGRAVING ON THE OUTER RING2. Original thickness is 4.5mm, this part is upgraded to 10.5mm for wider wheel track in order to run smoothly and more stable.3. The hex are designed to claw onto the wheels tightly and firmly.