Detent balls 3/32" heat treated,
440c stainless. Used for liner and frame lock folders. These things are tiny and you will lose a couple of these. Get some extra. 1/16" size detent balls are resting on the bottom Buffalo nickel to show scale.
Have a few of these on hand if the detent hole in your folder gets slightly too large or if you are making a stout size folder that needs to scale things up a bit.
The picture shows a couple of Buffalo nickels and a Hobo nickel I carved last year. A Hobo nickel is traditionally done with Buffalo nickels and changes either side into a different scene. Hobo nickels are now being done on all sorts of coins with many different carved pictures.
(note 1/16" detent balls are pictured)