Green wave. This plate first appeared on the roads of Ukraine in February 2020 as an experimental sign.
https://dorndi.org.ua/files/upload/%D0%BF%D1%80%D0%94%D0%A1%D0%A2%D0%A3%204100_1%20%D1%80%D0%B5%D0%B4%20%D0%BE%D1%81%D1%82%D0%B0%D1%82.pdf
Government of Ukraine