Homing beacon

The Homing Beacon is a unique weapon in Fallout 4.

Characteristics
This beacon is given to you by Captain Zao after completing the quest Here There Be Monsters. He gives you three beacons to be used wisely.

Once thrown, the beacon will blink and after a short delay a tactical nuke will hit exactly or near the spot where the beacon landed. This does not work in tight spaces, deep quarries or inside separate cells. The beacon is thrown at a speed faster than all other thrown weapons but will activate in mid-air and drop to a point where regular thrown weapons would hit the ground.

The nukes will not come from a vertical dive, rather the nuke will come at a about 60 degree dive from a random direction. If the beacon is used in an open area with buildings nearby, there is a chance the nuke will hit the roof of a building or a tree.

The nukes being launched look exactly like the nuclear missile inside the visible missile silo in the Yangtze.

The explosion will be similar to a Mini nuke in terms of blast radius and damage.

The beacon can be 'pickpocketed' into the inventory of an enemy and still work, however only one beacon can be active while in the enemies inventory.

Locations
This unique grenade/beacon can be acquired from Zao on the Yangtze after doing a quest for him.