unused Block of Four 4c-7c 1917 Issue (503, 504 two, 506, 507), margin or corner margin blocks, incl. 4c and one 5c block of six, all others are blocks of four, the 5c block of six and the 6c block of four both have foldovers creating 'wild' freak perfs. in the selvage and resulting in one misshaped stamp of each value, the 4c, 5c and 7c blocks of four have radically shifted vertical perfs. creating six 4c and three 7c freaks, a desirable lot