125 gram nuclear bomb? That is quite insane. The smallest nuke developed by USA weighed 20-22 kg. But it was abandoned as it was considered to be too weak 125gram is as good as hand grenade! Lol
Depends what the purpose is. Maybe they were testing them for the purpose of wiping out cities.
The 'Little Boy' which was dropped on Hiroshima had about 64 kg of Uranium filling in it. And it wiped out the city.
So 125 gram, if true, can still do a lot of damage (as should be the case which such materials) but it would mean much, much easier and accurate delivery.
But is it true? I don't know and I don't think so.