These cosplay props are some of my earliest work using Fusion 360, dating back to spring 2016. The shown prints are also from back then and might turn out better with the latest printers and slicing software.
The pouches have a hinged lid that opens so that the stun discs can be removed. The discs have a CR2032 battery that powers up two LEDs (I used red & blue) and is switched on using a reed switch. The reed switch is of an ON/OFF type, meaning that it has it can be used to switch on in the absence of a strong magnet as well as in the presence. I used this to my advantage so that the LEDs turn off when they are near a magnet (hidden in the pouch) and turn on when removed from the pouch. There are holes in the electronics housing for the switch (it's a fragile glass tube with a magnetic switch inside), two resistors (for the LEDs) and the battery.
The disc halves are attached using the electronics housing, but they also have holes for 2mm (or 1.75) diameter plastic rods (bits of printing filament), so that you can glue them together if you don't want to print the electronics block.
I used a bit of felt padding here and there inside the pouch.
The pouches are designed to be carried on a 38mm (1.5") tactical belt.