HLS-27 HEICO Fastening Systems HEICO-LOCK Washers , Manufacturer Part#: HLS-27 , Manufacturer: HEICO Fastening Systems , Brand: HEICO-LOCK Washers , UOM (Inch or Metric): Metric , Material: Steel , Finish: Zinc-Flake Coated , Bolt Size: M27 , Inside Diameter: 28.40mm , Outside Diameter: 42.00mm