What is this?
 

There is a positive and negative wire on my battery posts that I am trying to figure out. They are slip clipped on and easy to remove. I want to know if this is a necessary component or not. Like does it have to be connected for my car to start? The end wire was located under the battery not connected to anything. It almost looks like a connector for some add on device. Idk but would like to.
https://cimg2.ibsrv.net/gimg/mercede...b07d7e6638.jpg

The battery cable harness with the part number A0065400281 for the W221 Mercedes-Benz model is often referred to by alternative names such as:

1. Battery wiring harness
2. Battery cable loom
3. Battery wire assembly
4. Electrical harness for the battery
5. Battery wiring loom

These alternative names are commonly used interchangeably to refer to the same component.
Want to buy tight buffer cable you can visit https://www.mssdatasolutions.com.au/...tight-buffered