We start with an envelope of Ballistic Nylon so that what is in the pocket won't "print" on the outside of the garment.
The envelope is then specially lined with an industrial loop patch. Think of it as EXTRA Sticky- stuff the purpose of which is to allow the wearer an infinite orientation of holsters and mag pouches or flashlights and tools.
Why do that instead of a permanent, simple pocket? Because we over-build everything so that 10 years from purchase the gun isn't sagging away from the lining. What makes that important is that in a crisis you should be able to index to the grip immediately and without hesitation.
The pockets are on both sides. We have found that it's important to be able to add a mag pouch or speedloader to the other side. This balances the load and the jacket or vest hangs straight.
The Conceal and Carry Holster Pockets must be ordered at the time each style is built as it can't be retro-fitted later.