Empty 40 mm grenade cases used by Ukraine against Russian invaders.

Brought from the Ukraine front line.

The United States Armed Forces has created a plethora of different types of 40 mm grenades in both the low-velocity 40×46 mm and high-velocity 40×53 mm calibers which uses what it calls a high-low propulsion system which keeps recoil forces within the boundaries of an infantry weapon.

These are often used as shot glasses or candle holders.