The classic mailboxes, these units are manufactured with extruded aluminum doors in 5 different sizes and are designed to fit into the Rack Ladder System, Rotary Mail Centers or the 101C Modular Enclosures.

The Rack Ladder System is a rear loading modular system used most commonly by the US Postal Service. The rack ladders support five mailbox or parcel locker modules to form a column. One column requires 2 rack ladders and each additional column in the same bank requires one additional rack ladder. With a variety of unit types and sizes to choose from, the rack ladder system allows mixing and matching of units according to delivery needs.