The resulting barrel chest is a similar presentation in the upper torso to the appearance of the finger joints as someone ages with this condition. The ribs become fixed in their most expanded position, giving the appearance of a barrel chest, and this can also cause respiratory limitations during exercise.
In the overhand hold, the tactical ring aids in retention and keeps the light properly positioned for use. Alternatively the light can be quickly flipped into a back-hand hold allowing a two-handed grip on the weapon.
Police often use large flashlights like the classic D cell Maglite which, when held correctly, can double as a club and as a tactical light. The flashlight is held in the weak hand, with the back of the flashlight extending past the thumb.