Installing a mail slot in the exterior wall?

Through Wall Letter Chute External Wall Application Stainless Steel LBD Dimensions of letter slot: 45mm x 255mm Correspondence suitable: A4 and C4

This chute lets mail slide through the door or wall If you are worried about the indoor finishes of the mail chute, we have a solution! The stainless steel

through wall mail slot Through the Wall Letter Drop Slot with Chute · Vertical Through the Wall Mail Drop Slot

through wall mail slot sleeve Barska Through-The-Wall Mail Slot Drop Box Secure Locking Mailbox Adjustable Chute SKYSHALO Through The Wall Mail Slot Off Box