What is the preferred lockable single mailbox for postal carriers?

locked mailbox with slot
➡️【Mk.com】✅लाइव कैसीनो गेम✅, ऑनलाइन स्लॉट और बहुत कुछ का आनंद लें। हमारे ऐप्स एक सहज, उच्च-गुणवत्ता वाला गेमिंग अनुभव प्रदान करने के लिए डिज़ाइन किए गए हैं... 

This video is due to a request from my previous post on how to replace a mailbox lock There

Link to mailbox locks on Amazon: 3SHibcL Here

locked mailboxes with slot -- You could point out Section - Locked Box - of the Domestic Mail Manual

locked money box with slot locked mailbox? I live in condos and that happens once in a while If I find someone else's mail, I stick it in the slot beside their mailbox