1982 U.S. State Birds and Flowers First Day of Issue Covers

Got a couple of these 1982 First Day of Issue covers for the U.S. State Birds and Flowers series. This set has the Wisconsin and Wyoming envelopes. They've got the 20 cent stamps and the official Washington D.C. postmark from April 14, 1982. They're in okay shape for being over 40 years old, though the outer plastic is a bit wrinkled. Cool little pieces of postal history if you're into stamp collecting or just want something from the early 80s.