Handle with care is a paper note in Fallout 76, introduced in the Skyline Valley update.
Location[]
The note can be found in the Vault 63 organics sector, in the area connected to a metro line. The note itself is attached to a wooden post next to the train car with brains on the floor in the tram station near the entrance.
Transcript[]
HANDLE WITH CARE, DO NOT MESS THIS UP.
These items are to be delivered to the engineering lab. Any issues report them immediately to your line manager.