Which two countries flags are almost identical?

The flags for these two countries are almost identical—two horizontal stripes, red over white—but their dimensions differ; Indonesia’s flag has a height-to-width ratio of 2:3, while Monaco’s flag is 4:5. Both flags date back hundreds of years. Monaco’s flag is based on the heraldic colors in the shield of the Monegasque princely arms, and the flag of Indonesia dates back to its association with the Majapahit empire. Also similar to these two is the flag of Poland, although its stripes are reversed, white over red.