United States of America, Scott number 477, often referred as the War Issue

Interesting information, 477 was issued on 2 March 1917, it was replaced by 517 issued some time during May 1917, so only 90 days!

See scan



I've never found a 477 with a dated cancel between 2 March and 31 May 1917. I have other 477's but without the dates as stated.