**** 軽自動車：KEI-JIDOUSHA；light weight car or K-car ****
After the WWII, Japanese government made a new "light weight" class of car to encourage the car makers could sell low price cars. At the moment, engine size was restricted less than 360 cc.
The "K:light weight" standard is revised sometime and now it is defined 660 cc engine, 3.4 m in length, 1.48 m in width and 2.0 m in height.
Here is the legend of 360 cc "SUBARU 360"(from Wikipedia).
Rear view (Wikipedia)
K-car itself is very useful for row cost commuting or carrying light things. And also K-car makes the base of re-modeling.
Here the old man equipped SUZUKI 1100 cc engine on K-car as "mid-ship". These re-modeled car is illegal to use on public road.
You can find K-car on the road by the yellow "number plate" (for personal use). Black "number plate" with yellow letters also mean K-car for business.