Tandy released a Multi-Pak Interface which allowed switching quickly among four cartridges mounted at the same time. This was similar in concept to the Model I's Expansion Interface.

The TRS-80 Color Computer Multi-Pak Interface allows you to connect up to four Color Computer Program Paks or Interface Controllers to your Computer at once. Then, when you're ready to change from one Program Pak to another, simply select another "slot".

Frequently used Program Paks will no longer have to be removed and reinserted for use. You can use them over and over without having to change the setup or continually change cartridges.

Note that Slot Selection on the Multi-Pak Interface can be performed via "hardware" (actually moving the switch) or "software" (by "POKEing" a memory location from BASIC).

The Multi-Pak plugs into the slot of expansion of the Color Computer (cartridge port) and expands it to handle up to 4 cartridges interchangeable and can be used one at a time without having to put out one another, this exchange of the 4 slot can be done without shutting down the computer, but sometimes need to use the reset.

There were four models: 26-3024 Grey, 26-3024 White, 26-3124 White and 26-3124A White.

Our unit is the 26-3124 which is in excellent condition with the original box and was very kindly donated by Andy Taylor of RetroComputers.Online