The United States Save Vanishing Species semipostal stamp (Scott B4) has returned to sale at post offices nationwide.

U.S. Postal Service spokesman Mark Saunders told Linn’s Oct. 14 that the stamp is available for purchase again through the USPS website and at post offices nationwide.

Sales of the stamp have been extended through Dec. 31, 2018.

The stamp sells for 60¢, which includes an 11¢ surtax above the 49¢ first-class letter rate. The surtax is then donated for multinational species conservation.

The stamp initially sold for 55¢ from September 2011 through Dec. 31, 2013. Of the 100 million stamps printed, only 25 million sold before it was removed from sale.

Sen. Rob Portman, R-Ohio, pushed legislation to continue sales of the semipostal, which resulted in the remaining stamps returning to sale.