Lots to like about this cover. Patriotic cachet cover for Army Day, April 7, 1941 mailed on that date from McCellan Air Force Base, California to Plainville Kansas. Missent to Plainville Massachusetts (with Dead Post Office mark from that town). Also, unusual "missent to Plainville, Mass." auxiliary mark across top of cover. Someone wrote Kansas on the cover and assume it was forwarded there. No additional marks on back.