What are colored decorative stripes on the sides of the uniform trousers called?

The broad, mostly colored decorative stripes on or next to both outer seams of certain uniform trousers are called lampasses. In contrast to the narrow, cord-like piping, lampasses are strips of fabric that are sewn over or next to the outer seam of a uniform trouser leg.

In civil trousers, the corresponding decoration is called the galon. The word lampas comes from French, where it denotes heavy silk or damask-like fabric.

Originally part of European men's fashion at the beginning of the 19th century, lampasses were also used in the uniforms of various German states. In Prussia, they were worn by officers on both sides of the piping from 1815. There they had a badge color, so for regiments with red badges also red lampasses.

From 1832 to 1896, in Prussia, they were reserved for generals (red double lamps) and general staff officers (crimson lamps). With the new gala trousers introduced in 1896, they became common again for almost all officers. Only the hussars did without the lampasses, as the jewelry of the Schoytaschierung on their trousers was sufficient.