HLB-3/8 HEICO Fastening Systems HEICO-LOCK Washers , Manufacturer Part#: HLB-3/8 , Manufacturer: HEICO Fastening Systems , Brand: HEICO-LOCK Washers , UOM (Inch or Metric): Inch , Material: Steel , Finish: Zinc-Flake Coated , Bolt Size: 3/8 Inch UNC , Inside Diameter: 0.410 Inch , Outside Diameter: 0.830 Inch