1 Standard: DIN, BS, IFI, JIS, ISO,GB,ANSI,ASME,Non-Standard
2 Size: M3–M76
3 Material: 
  1) Carbon Steel
  2) Alloy Steel
  3) Stainless Steel
  4) Brass
  5) Aluminum
      etc.
4 Finish:
  1) Zinc Clear
  2) Zinc Yellow
  3) Black
  4) Nickel-plating
  5) Tin-plating
  6) Chrome- plating
  7) Dacromet
  8) Mechanical Galvanizing
  9) Hot-dip Galvanizing
5 Type
  1) Spring washers
  2) Flat washers(plain washer,IFI,ASTM)
  3) Lock washers
  4) Star washers
  5) Square washers
  6) According to your request