Filling out a form in Spanish

Question

How would I write: 1) Post Box Number 2) Not Applicable

Thanks

Answer 1

I know:

Apartado Postal # 75

Not sure about the abbreviation of N/A

Not too sure that there is an abbreviation but it stands for "no interesa". - Eddy, Oct 7, 2011

Answer 2

Or "casilla postal"