KD Fasteners, Inc.® can supply the hardened flat washer that you need. We offer both domestic and import hardened flat washers. We also carry them in standard and metric sizes. Our off the shelf items include the following:

hardened steel washers

  • USS (in this size we offer standard and extra thick)
  • SAE (in this size we offer standard and extra thick)
  • F436 structural flat washer
  • Our off the shelf metric line comes in 200 HV and 300 HV harden steel.
  • Din 125 (flat washer)
  • Din 433 (small series)


We carry them in stock in plain, zinc, zinc/yellow, and hot-dipped galvanized. If you are looking for plating specifications not listed, we can plate per your needs.

Our hardened flat washer line also includes made to order specials. We can also make per your size and hardness. Our specials include both metric and standard sizes. We are able to make hardened washers to your print and the material hardness.