Made using Delrin material. These pillar ball retainers have proven to last a lot longer than the stock models.
We have noticed that with all pillar ball style vehicles that the stock plastic injected retainers will wear a flat spot at the top of the insert.
due to the part floating in the knuckle this part rotates and eventually will back out the pillar bar retainer nut.
Since the delrin is a lot harder material , it will resist wear a lot better than the stock insert.