だい よん しゅ郵便 ゆうびん ぶつではありません
dai yonshu yūbimbutsudewārimasen

Noun
Desu Copula
Negation Auxiliary

The polite negative form of 第四種郵便物

1. It is not fourth-class mail.; It is not registered mail.

Negative
Polite
Formal Register