
M6 - M30 Carbon Steel Castle Nut Heavy Machine Nuts and Bolt. OEM/ODM Customization: Professional manufacturer accepting OEM and ODM services with competitive pricing. Strict Quality Control: Professional QC team inspects every item from production to packaging to ensure quality. Wide Material Range: Available in Carbon Steel grades 4.6 to 12.9, DIN, ANSI, JIS, and ISO standards. Multiple Surface Treatments: Options include Zinc Plated, Black Oxide, Galvanized, and various other finishes. Free Sample Available: Free samples provided for standard fasteners to test and check quality before order. Experienced Manufacturer: Over 30 years of experience with a 30,000-square-meter modern production base. Fast Delivery Service: Shipping department ensures faster delivery and well-protected goods for all orders. Global Market Reach: Products exported to North America, Europe, Asia, Africa, and other global markets.