5mm hex bolts and a 6mm hex nuts Designed with precision-machined M8.5 steel bolts and 5mm hex heads, providing secure fastening and easy installation with common cycling tools. Engineered for compatibility with double chainring setups and inner chainrings, these silver aluminum bolts maintain aesthetic appeal while offering reliable strength. Sleek silver finish complements various bike styles and components, making them ideal for both performance upgrades and aesthetic customization. Innovative threading and engineering minimize stripping and loosening during intense rides, ensuring your chainrings stay securely in place across challenging terrains.