Multi Holsters 3AT IWB Appendix Tuckable Holster 3A/T (IWB) stands for Appendix, Ambidextrous, Adjustable, and Tuckable. Made of 1 solid piece of .08" thick Kydex. All edges are rounded next to the body for maximum comfort and concealment. The fully adjustable belt flex loop can be adjusted for height and cant. This holster is totally ambidextrous. It ships with the belt flex loop set-up for right-hand but can easily be unscrewed and installed on the other side of the holster for left-hand users. This holster is "tuckable" which means your pistol can be easily concealed while wearing a dress shirt or other shirt tucked into your pants.