This housing is used to enclose 1157 dual filament bulbs for load testing circuits in class. While many reputable vendors have similar models, none have control of the market.
Use the file if you don't want to pay ~$40 from a vendor; if you don't have a 3D printer, buy from the vendors.
You will need a 1157 socket with harness and terminals to connect to the circuit being tested for potential power issues.
The author marked this model as their own original creation.