461S0500 M5 Spring Washer Stainless Steel JIS
Made in Japan.
d=ID 5.1mm +0.4
D=OD 9.2mm -0.5
Thickness 1.2mm
Max Thickness 2.8mm 
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 461S04500