1928, airmail stamp 5 C. (Michel. No. 310), special collection with margin stamps on approximate 240 first flight covers, as well approximate 120 covers with plate numbers (z. T. Multiple on a cover) as well various stamps from corners of the sheet (in part with marginal inscription "A. B. " respectively "W. E. S. ") and stamps with upper margin and inscription "top", going through good condition