A friend had been wanting a Grenade. I had seen a few designs already, and really liked some, but wanted to add some additional functionality.
Not to completely reinvent the wheel, I incorporated a few of those designs and made the thing modular.
After many Boolean operations, and due to poor planning, I accidentally created a locking feature with a ridge on the opening of the grenade body.
I got griped at for taking this into a public place.. I really didn't consider that either..