A builder’s plate indicates who built a particular piece of machinery, as well as the the model number, serial number, and date of manufacture. Here are some examples from the rolling stock of the railways of Russia and Ukraine.
ЭД4МК class Электропоезд (electric multiple unit) operated by Russian Railways.
Built by the Демиховский машиностроительный завод (Demikhovo Machinebuilding Plant)
EЖ electric multiple unit on the Kiev Metro.
Built by the Мытищинский машиностроительный завод (Mytishchi Machinebuilding Plant)
Built by the Демиховский машиностроительный завод (Demikhovo Machinebuilding Plant)