Transnistria is a breakaway territory located mostly on a strip of land between the Dniester River and the eastern Moldovan border to Ukraine.
Tiraspol is the second largest city in Moldova and is the capital and administrative centre of the unrecognized PMR. Tiraspol is a regional hub of light industry, such as furniture and electrical goods production. (source)
Since its declaration of independence in 1990, and especially after the War of Transnistria in 1992, it is governed as the Pridnestrovian Moldavian Republic (PMR, also known as "Pridnestrovie"), an unrecognized state which claims the territory to the east of the river Dniester, the city of Bender and its surrounding localities located on the west bank.
The Republic of Moldova does not recognize the secession and considers PMR to be part of Moldova's autonomous region of Stînga Nistrului ("Left Bank of the Dniester"). (source)
The stamps of Transnistria are not recognized outside the country and are valid only for domestic service within Transnistria. International mail and mail to the rest of Moldova requires Moldavian stamps. (source)
Thank you Jaroslav for adding a new territory to my collection!