Which of the following is NOT a cleaning material used for firearms?

Household bleach is not a cleaning material typically used for firearms. Firearm cleaning materials, like gun cleaning solvents, brass brushes, and cleaning patches, are specifically formulated and designed to safely clean and maintain the components of guns without causing damage.

Gun cleaning solvents are designed to dissolve carbon buildup and other residues that accumulate during shooting. Brass brushes, made from brass, are effective at scrubbing the insides of gun barrels without scratching the metal. Cleaning patches are used in conjunction with cleaning solvents to wipe down the barrel and other parts, ensuring that they are free from dirt and debris.

In contrast, household bleach is a harsh chemical that can corrode and damage the metal components of firearms. It can also leave harmful residues that adversely affect the functioning of the gun. Because of these properties, bleach is not suitable for firearm cleaning, which is why it is the correct answer to identify as the material that does not belong in this category.