We go through training on this exact subject. Tow Zone is correct, it could be any kind of a weapon that could cause the driver to be badly hurt with anything. If it is a J Hook, chain, spreader bar, knife, ect. with proper training and use, the perpetrator can easily be dissarmed. Then jump in the truck and move a safe distance away and by all means then (and only then) call the proper authorities, but stay in the area so you can sign the complaint. DO NOT call the authorities in front of the customer as this will only excalate the perp's anger!
I carry a 9mm hand gun in my truck, and many people ask me why. They tell me I am only escalating the problem. Welllll I was a US Navy Seal for 12 years including during the Korean war. (I don't care what everyone says, KOREA WAS A WAR!) I hold a Brown Belt in Karate, a green belt (5kyu) in Judo,
and I can disarm most combatants, but NONE of the above ever taught me how too out run a 357 bullet, not even if I manage to get to my slow truck.
All that being said I must add that I feel that most ugly situations can be resolved without any physical confrontation through cool minds, tone of voice, and politeness (is that even a word?). I have observed in my 82 years of life that every once in a while some of us driver's have a "short fuse". If that's your case, you need to find a different line of work, preferably one that does NOT require dealing with the public !
Just the ramblings of an OLD Cowboy/Tow Truck Operater, so PLEASE don't holler at me, dat ain't nice!! 🤠