Inert Grenade Bomblet

This was in my grandfather’s belongings. I’m told it’s an inert training bomblet from a cluster bomb. The ‘detonator core’ worries me, though. I have to wonder why a training round would need one? That’s my mystery, I guess. The community responses to an identical item helped me identify it (thanks!). As mine is disassembled, I offered to show you all what it looks like on the inside, and here it is. I hope you enjoy it.