Import Grade5/8 Flat Head Square Neck Bolt Black — Buy in Bulk from Supplier in China

This Grade 5/8 flat head square neck bolt in black finish is a heavy-duty carbon steel or alloy steel fastener designed for applications requiring high shear strength and a flush surface. The square neck under the head prevents rotation when tightening, making it ideal for wood-to-wood or wood-to-metal connections. It meets DIN, ANSI, JIS, and IFI standards, with thread options including UNC, UNF, and metric, and is available in sizes from M4 to M20 and 3/8 inch to 7/8 inch.

The bolt’s material can be carbon steel, alloy steel, or stainless steel, with surface treatments such as plain, zinc plating, hot-dip galvanising, DAC, or Geomet coating to enhance corrosion resistance. The black finish typically indicates a phosphate or oxide coating for additional protection. Standard grades for such bolts often include Grade 5 or 8, which correspond to tensile strengths of 572 MPa and 800 MPa respectively, though the exact grade should be confirmed with the supplier.

These bolts are commonly used in heavy machinery, structural steel frameworks, and construction projects where vibration resistance and load-bearing capacity are critical. Buyers in industrial, automotive, and infrastructure sectors often source them in bulk, with packaging options including small boxes, poly bags, cartons, and pallets. Confirm delivery timelines, as lead times may vary from 30 days depending on order quantity.

Shanghai T & Y Hardware Industry Co., Ltd. is based in Songjiang, Shanghai, with its office at Rm. 509, Building 1, No. 388, Xinfu Rd. The company operates as an imported-tier supplier specialising in fasteners and hardware components for industrial and construction applications. Its product range includes bolts, screws, and custom fasteners tailored to international standards such as DIN, ANSI, JIS, and IFI.

The supplier offers flexible trade terms, including TT, LC, or Western Union for payments, and provides delivery timelines starting from 30 days, depending on order volume. The response rate and average response hours are currently not available, which may require direct contact for urgent inquiries. The company’s focus on standard-compliant products and multiple surface treatment options positions it as a practical choice for buyers needing reliable fasteners.