Bought for a project and never used because plans changed. The part has not changed over the years.
This is part of a Tech Lighting (now called Visual Comfort) monorail track lighting system. Many of the parts can be found here:
https://www.visualcomfort.com/architectural/monorail/
Example below with tech info:
https://www.build.com/tech-lighting-700moa24/s305261
Check out my other cheap, complimentary Tech Lighting Monorail parts.
Returns accepted within 30 days. Please reach out if any problems.