Across Flats (Width): Max 0.562″ – Min 0.545″ Color: Yellow Color May Vary: Color and sheen may vary Condition: New Diameter: 5/16″ Drive Style: External Hex Thread Direction: Right Hand Fit: 2B Internal Thread: 5/16/2018 Material: Brass Part Number: 046737863907 Product Type: Cap Nuts Size System: US Size Type: Regular System of Measurement: Inch Thread Direction: Right Hand Thread Pitch: 18 Per Inch Thread Size: 5/16″-18 Thread Standard: UNC Thread Type: Coarse Tolerance (IFI): Actual measurements may vary slightly /- depending on production run within IFI Tolerances Weight: 1 lb Hex nut with a closed end Domed thread to protect external thread Low Crown Most Popular style Easily Removable Aesthetic finished look Also known as an Acorn Nut, Cap Nut, or Dome Nut