A aluminium cleaning jag sized for 12 Gauge shotgun barrels. A jag holds a cleaning patch tightly against the walls of the bore, so each pass wipes out powder fouling, solvent and dirt more thoroughly than a loop. Aluminium is light and softer than barrel steel, so it will not scratch the bore. Wrap a patch around the jag, screw it onto a cleaning rod with a matching thread and push it through the barrel, using solvent-wet patches first and dry patches until they come out clean, then a lightly oiled patch to protect against rust.