Vintage 1970s Rockwell Battery Operated/Electronic Handheld Computer & Calculato

Produced by Rockwell International in the 1970s. This is Model 21-R of their series of computers/calculators. Comes with a 7.5 ft AC adapter/battery charger and a brown leather carrying case. The box is very worn but both the calculator, case and battery charger are in very good vintage condition. The batteries are soldered in. Not sure if they are working and if they can be charged. The unit does work when plugged in. The digital display is red.