These lights are designed for your rafters inside Round Houses.
They come in sets of 2. Each one is 1" (25mm) long with a 10mm lamp shade attached.
They take a 1.5mm fiber that you will provide and can be inserted and bent to your own design requirements. See https://www.dwarvin.com/blogs/stories/bending-fibers
These lamps are made from thin walled metal tubing and a lamp shade.