The ink cartridge is the long white or clear tube in the middle of the pen.

Don’t bend the area with the screw threading, or else you won’t be able to put your pen gun back together.

The bent edges on the tube should hold the plastic piece in place. If not, go back with your pliers and bend the edges further.

If the ink cartridge doesn’t fit through the tip, remove the pen tip from the tube by unscrewing it or pulling it off with a pair of pliers.

Only point the pen gun at a target. Avoid shooting any person or animal since you could cause them harm. Reset the gun by pushing the plastic piece back into the top section and reloading the ink cartridge.

Any pen will work when you use a rubber band.

Only try to cut the tip if the pen is made of plastic. Use a utility knife if the scissors don’t cut through the pen tip.

If you have trouble feeding the rubber band through the holes, bend a paperclip into a hook and use it to guide the band.

Avoid aiming the gun at a person or animal since you could cause them harm.