わたくし書箱 しょそう番号 ばんごうなら
watakushisho sō bangōnara

Noun
Da Copula

The "-nara" conditional form ("if/when…") of 私書箱番号

1. If/when it comes to my PO box number…; Regarding my PO box number…; As for my PO box number…

Nara Conditional
Computing