The 4P's video monitor is 9" in size, compared to the Model 4's 12". The smaller size, and sharper dots, produce better video output. The computer is compatible with popular internal Model 4 peripherals, and has a slot for an internal modem board. The Radio Shack modem uses its own proprietary command set and only supports communications at 300 baud. Teletrends produced a 1200 baud that uses the Hayes command set.
Tandy discontinued the 4P by early 1985, stating that "even though you won't find a more enthusiastic and devoted group of owners than our Model 4P folks, transportables just weren't moving well for any company that also sold a desktop version".