This will get the side lights on your Silverado or Sierra tow mirror to work as both a dome light and a reverse lamp. This is ideal because the light can work as approach lighting when unlocking the truck, but also as a reverse lamp.
The video below will go over how to wire it in.
video was very helpful on install. glad i chose this option.
I have a tahoe with tow mirrors and its very helpful at night with the kids getting in and out
So far so good.