First Day Covers of the Norse-American Issues dated May 18, 1925 by Slogan Cancels. These examples are addressed to Bill Schneider in Rahway, New Jersey, the 2 Cent from Washington, D.C. and the 5 Cent from Minneapolis, Minn. The 5 Cent is a margin copy and both covers are hand-stamped "First Day of Issue" with receiving marks on back. The 2 Cent envelope has a vertical crease at left. 
Sent via USPS and combined shipping is available.