This is a rare and historic discus grenade from World War I introduced by the German Army.

The German engineers believed this design would make the grenade more aerodynamic, allowing soldiers to throw it farther than traditional grenades. Soldiers were trained to hurl it with a spinning motion, mimicking the throw of an athlete. But in practice, it was difficult to throw accurately, especially under the chaotic conditions of trench warfare.

The discus grenade used a friction ignition system, with a delayed fuse that allowed the soldier time to throw it before detonation but this system could sometimes be unreliable, either detonating too early or failing to explode at all."

Although the design was cutting edge, it had some major drawbacks. The discus grenade was heavy, making it difficult to throw far and accurately, limiting its effectiveness in battle."

Due to these challenges, the discus grenade was not as widely used as the more reliable German stick grenade. However, it did see use in certain situations during trench warfare

The discus grenade has become a rare collector’s item and remains a fascinating example of the military experimentation that defined World War I.