This is your basic Shackle with a tiny difference. It has a .25" (1/4") offset. When you combine 2 you get a .5" (1/2") offset so you can change your Leaf springs with having to change your Shackle Hangers. Think of a CJ running Wrangler springs, the Wrangler spring width is 2.5" and the CJ is 2.0" and this is a very common swap. They, like all of our Shackles are made of .375" (3/8") A50 Plate Steel and have a .75" hole for reinforcement if you desire. They are sold each.