MOLLE Flashlight Pouches (also sometimes called flashlight holders or flashlight sheathes) allow you to easily carry a small flashlight on your MOLLE vest, backpack or other compatible gear.
Most of these flashlight holders are designed to carry small, double A battery sized flash lights.
They generally come in 2 varieties. The first could officially be called a flashlight pouch, since it has a flap that goes over the flashlight and velcros to the pouch.
The second type more closely fits the description of being a flashlight sheath, and is open topped but tighter fitting.
There are also some manufacturers of tactical flashlights who make specially designed flashlight holders for their flashlights. These are specifically designed to work only with their flashlight, and won’t work with other brands.