461S0600 M6 Spring Washer Stainless Steel JIS
Made in Japan.
d=ID 6.1mm +0.4
D=OD 12.2mm -0.5
Thickness 1.6mm
Max Thickness 3.8mm 
Kawasaki part number is for reference only, 
this is a Genuine JIS washer from our supplier in Japan.
Ideal replacement to the original
Equivalent to Kawasaki Part 461S0600