mail slot

i'm install MSL6030 i'm seen user guide manual but not understand mail slot i have 5 LTO tape slot is empty and 0~4 slot is tape

Gibraltar Mailboxes® Rubbed Bronze Mail Slot Ship To Store

what is a mail slot Mail slots are constructed of solid brass or stainless steel material and available in two popular sizes Interior & exterior sides of the mail slots have

what is a slot game Description · A slot in a wall or door through which mail is delivered · A box attached directly to the building · A box mounted at or near the street; A