This will invert or evert the rearfoot with dense extrinsic heel posting material. A neutral heel post will align the foot into calcaneal vertical and offer medial and lateral stability. A rearfoot varus post will have thicker material on the medial aspect of the heel to help correct over pronation. A rearfoot valgus post will have thicker material on the lateral aspect of the heel to correct over supination.
All LEO Lab shells are intrinsically corrected to neutral. Extrinsic posting is added beyond neutral for more functionality.