PTFE Coated Hex Head Bolt, Standard ASTM, Material A193 B7, Size 5/16 to 4 Inch, Length 30 to 3000 mm Name: PTFE Coated Hex Head Bolt Standard: ASTM Material: A193 Size: 5/16 to 4 Inch Total Length: 30 to 3000 mm Grade: 10.9 Application: Oil Pipeline, Machinery, Chemical Industry, Building Qishine Pipe Fastener Gasket Co., Ltd. (https://www.qishine.com/) has always been at the forefront of the pipe fittings industry. Qishine is a professional manufacturer of pipe fittings. Our products include gaskets, bolts and nuts, flanges, pipe fitting, valve and steel pipes.