In the store I worked in decades ago they were (LCD not e-ink) updated by two means IR and radio. Not sure why it had both. They were also kind of an ecological

In the store I worked in decades ago they were (LCD not e-ink) updated by two means IR and radio. Not sure why it had both. They were also kind of an ecological disaster. Getting crushed in the back of the store, tons of batteries... We probably replaced tens of them every freaking day (really large store).