Spacers - which ones would you recommend?

[ptolemy]

I got a Pila charger for 18650's that my friend gave me but I also have some of the cr123's that I use for pelican 2330.

I would like to be able to charge cr123's in Pila charger.

If i want to stay away from the magnets, what other options do i have for reliable, reusable spacers? Preferably something I can make (and I generally cannot make anything).

If id o get the magnetic spacers (if no other choice) what is the safe distance to store them from watches, etc?

Thanx;>

 

[Tohuwabohu]

I use a simple metric M3 screw:

The 2 countered nuts act as a stop.

 

[ptolemy]

I use a simple metric M3 screw:

The 2 countered nuts act as a stop.

thats probably as idiotproof as i am looking for

i wonder if others have other advice