usually has a petty tough time of things, ending up with a damaged and chewed up surface, as well as being corroded.
Thankfully it is inexpensive enough to replace, and to keep a spare in your toolbox, just in case!
For other useful bolts and fasteners for use now, or in the future browse the online schematic or Products Gallery for your model, and make sure you have that important part when you need it most!
Some other related washers you may wish to consider ordering at the same time:
Factory specified parts are frequently good value and ALWAYS great quality. Use genuine Japanese manufactured fasteners - why take the chance with any other make!