The deadline for exchanging pre-2005 currency notes of various denominations, including 500 and 1,000 rupees, has been extended by another six months till June,30, 2015. In a statement, the central bank clarified that all such notes will continue to remain a legal tender. These notes can be exchanged for their full value, it added.Currency notes issued before 2005 do not have the year of printing on the reverse side. In notes issued post 2005, the year of printing is visible at the bottom on the reverse. Post-2005 notes have added security features and help in curbing the menace of fake currency.Seeking cooperation for withdrawing pre-2005 currency notes from circulation, RBI has asked the public to deposit the old design notes in their bank accounts or exchange them at a bank branch convenient to them.