sierrax
+1y
You leave everything on your truck as it is. The bags bolt on the leaf springs and to your frame above or near the axle. They are intended to be a helper bag for carrying large loads or a trailor but you can use them for lift/lowering. Usually, you run a mono leaf or your main and overload leafs with this setup for lift/lowering.
As gravity5 said, it is way cheaper than any link system and if you do upgrade to a link, you can use all of the parts again. I had one for about a year on my fullsize and I loved it, but them again I went from a static drop to the bags.