Mailbox Options To perfectly meet your needs, we offer many options for each of our mailboxes. The following page displays the complete list of options, classified in distinctive categories. Every adjunct is accompanied by a code, a description as well as a photo. At Cendrex, we work hard to meet your needs! Mail and key return slots Locks and keys Other options Mail and key return slots CPGEFI-04 Mail slot Mail slot with an opening of 4 3/8″ X 3/8″. CPGEFI-05 Mail slot Mail slot with an opening of 10″ X 3/8″. * Only for horizontal mailboxes. CPGEFI-06 Key return slot for parcel box Key return for parcel box 2″ X 5/8″. Locks and keys CPGEQC-06 Master lock Master lock and keys for internal mail. CPGEQC-08 Master lock for Canada Master lock for Canada Post to internal mail conversion. CPGEQC-04 Postal lock Postal lock with 3 keys. CPGEQC-05 Additional keys Additional keys for mailboxes. CPGEQC-03 Blank keys Blank keys for postal lock. Other options F0EPQC-01 Pin hinges Pin hinges CR 1/8″ X 12 ft for mailboxes. CPSAQC-11 Bracket for Canada Post Bracket for Canada Post horizontal mailboxes. CPACFI-03 Identification on grey gravoply plate Identification on grey gravoply 5/8″ X 2″. CPSAQC-15 Identification holder Identification holder for mailboxes. CPGEFI-02 Door bell Door bell for vertical mailbox. CPGEFI-07 Trim Aluminum anodized trim.