What Are Holster Wedges? A holster wedge is a simple yet revolutionary accessory for individuals who practice Inside-the-Waistband (IWB) or Appendix Inside-the-Waistband (AIWB) concealed carry. Typically crafted from foam (often memory foam) or sometimes Kydex, these small, angled devices are attached to the backside of a gun holster—the side th