I have the main unit.
type calculator
country Japan
year 1972
display 10 digits, red LCD
power 4*AA batteries
The Canon Palmtronic LE-10 — Early LED Calculator
The Canon Palmtronic LE-10 was one of Canon’s early pocket calculators using LED display technology — part of the pioneering wave of handheld electronic calculators that transformed arithmetic in the early 1970s. Before pocket calculators, even simple arithmetic required mechanical calculators or laborious manual calculation. Canon’s Palmtronic series brought instant, accurate calculation to a pocket-sized format, establishing the calculator as an essential everyday tool. The LED display’s characteristic red glow became the defining visual signature of early calculator technology.