This is very important to remember

When you buy genuine Provisional Air Mail 45 Mk carmine OPTs, please, notify the big difference in the issued quantities!

45 Mk. carmine OPT  
 Distance between OPT 5 and M = 1,25 mm

Day of (1st printing)-issue: October 1, 1923 Perforation: Imperforate 

Issued: 9.900

 The total length of the OPT = 23 mm

45 Mk. carmine OPT 
 Distance between OPT 5 and M = 2 mm

Day of (2nd printing)-issue: November 9, 1923 Perforation: Imperforate 

Issued: 3.234 only

 The total length of the OPT = 24 mm