You used to be able to carry around as many lock-picking bobby pins as you wanted in Fallout 4, but Bethesda’s newest game has assigned a weight to them. And they are way too heavy.
LukyJoeKokomo did the maths (via PcGamesN), and worked out that if a packet of 100 bobby pins on Amazon weighed 2.4oz, then each pin would weigh slightly less than 0.024oz or 0.0015lbs each (because you’ve got to allow for the weight of the packaging).
In Fallout 76, though, ten bobby pins weighs a pound, making each individual digital pin over 60x heavier than an actual one. Indeed they’re so heavy it works out that 60 pins weigh the same as a mini nuke.
Fallout 76 has tried many new things, but over-encumbering you with hairpins is the one I’ll be remembering.