Allows rotation of the denture attachment. No need for parallelism. Provides the strength of a solid shank post.1-4 Vents hydrostatic pressure of cementation, for easier post placement and a more secure cement interface. Offers the ability to remove a post, should there be a failed root canal, without surgically widening the canal.Guides Retreatment Drills for safe post removal and access to the apex. Locks-in post cement to provide high retention.