This is a Dwarvin DV101-2NP Lamplighter 1 without a power supply. This item can be used with all scales.

The Lamplighter System is an innovative system using fiber optics. 

Based on using a very intense light system underneath the train table (or doll house or whatever), fibers are then run into the space to be illuminated.  The light source is 30+ times brighter than the typical LED used in hobby applications, which allows the lighting of buildings and creating street lamps that will really glow well.  The lighting of even a single fiber is intense. 

The light output of a single 1.5mm fiber is equivalent to a typical 20mA LED.
To light a structure all one has to do is snip off the appropriate length of an optical fiber, insert one end into the Lamplighter box and run the other end up through a hole into the structure.  A grommet grabs hold of the fibers so they are held in place.  Each Lamplighter box allows you to light up multiple structures, making the addition of lights into many structures very simple. 
 
How many fibers can you fit into the box?
- 13 of the 1.5mm fibers
- 28 of the 1.0mm fibers
- 20 of a mixture of the above two fibers.  

For HO layouts we recommend using 1.5mm diameter fibers to light buildings, and 1.0mm for street lamps.
For N Scale layouts we recommend using 1.0mm diameter fibers to light buildings, and 0.75mm for street lamps.
For O Gauge layouts we recommend 1.5mm fiber for both buildings and street lamps.
You can use 0.75 and 0.5mm for lighting trees and other applications.  

What do you get?
- Lamplighter 1

Dimensions:
L: 4 7/16"(11.2cm)  W: 2 3/8"(6.1cm)   H: 1 1/4" (3.2cm)
Length with Flanges: 5 7/16" (13.8cm) 

Benefits:
No wiring needed!!
Add light to structures in a matter of seconds.
Cost effective when compared with other commercial systems.
No heat is dissipated in or near the buildings being illuminated.
Lighting effects are limited only by your imagination