Flange bolts have a one piece hex washer head bolt with flat bearing surface. The flange eliminates the need for a flat washer and helps compensate for a misaligned hole. When used with a proper class flange nut, the bolt system resists bolt slippage by distributing the clamp load over a wide area. Flange bolts should be used with the corresponding hex flange nut to achieve the best load distribution.. ACQ Rated Fastener: No. Fastener Color: Silver. Fastener Length: 2 in. Fastener Material: Steel. Fastener Plating: Uncoated. Fastener Type: Hex Bolt. Grade: Grade 5. Measurement Standard: SAE. Measurement System: Inches,Metric. Package Quantity: 10. Product Weight (lb.): 0.0602 lb. Thread Pitch (mm): N/A - Inches Fastener. Thread Style: Coarse Thread. Threads Per Inch (TPI): N/A - Metric Fastener. Head diameter (in.): 0.3125. Size: 5/16 in. Fastener Length: 2 in. Grade: Grade 5. Size: 5/16 in. Measurement Standard: Metric. Package Quantity: 10. Measurement Standard: Inches. Fastener Type: Hex Bolt. Thread Style: Coarse Thread