Waveshare 1.64inch Square E-Paper (G) Display, 168x168, Red/Yellow/Black/White

Most e-paper displays are limited to black, white, and sometimes grey, which rules out colour-coded status indication - a red warning versus a yellow caution versus a routine black-on-white update all end up looking the same. This 1.64-inch square panel breaks that limitation, supporting red and yellow alongside the standard black and white, so a status display can actually use colour to communicate urgency or category at a glance. Like any e-paper display, it holds its image with zero power draw once written, making it suited to a battery-powered status board that updates occasionally but needs to stay legible for long stretches in between.