This is a bag of railroad spikes.
They are used to add authenticity to model train setups.
This is a 1/64 drill bit.
The 1/64″ drill bit is usually not included in a set of drill bits. I purchased this one separately.
Take the 1/64 drill bit and drill a hole in the second fret of a banjo’s fifth string.
Lightly tap a railroad spike into that hole with a small hammer. You want to leave enough clearance between the top of the spike and the fretboard so the string can slip under easily. They should be some down pressure as well.
Now you can play your banjo in the Key of A and your fifth string will sound an A. Repeat procedure for Key of B if you like.
What will I do with 499 HO model train railroad spikes?
Oh, I will find a place for them. You just never know what you might need one day. :)