Is it possible to soundproof a door with a mail slot?

Is it possible to soundproof a door with a mail slot? door mail slot cover Luckily my awesome father in law created this lovely mail slot cover with door It acts as a fabulous draft barrier against the winter chill door mail slot collection box Mail slot w door & interior trim 13'' w13'' interior trim Call For Price Home Accessory Mail Slot Cover Call For Price! MSC105 Mail Slots View

door mail slot collection box Since 1993, The Mailbox Shoppe has been a leading supplier of mail slots, letter slots, and letter box plates > Covers door opening 11 wide x 2 high maximum

door mailbox slot Mail Slot - Flap & Hood They attach to your door and cover your internal letter box flap via a Velcro style system There are two sticky back strips supplied that you attach to