Defrost is a different issue. "Needing" it is up to the truck owner. Some old trucks had heaters and defrost. Some did not. It was not standard equipment. I believe they had defrost vent slots and a delete plate on firewall for a heater. This is for an accessory/dealer or factory heater. Some extra holes/work was needed.
If a person has no heater and no built-in provisions (that would be a pretty old truck), then that is a question for another post. If they do have those provisions, the best bet is original heater with defrost flapper.
You are correct, I don't see an actual defrost mentioned by Coldmaster in the kits with heater box. Their heater is just a universal box they thru in. It does have 4 outlets. Some could be plumbed to the windshield. There are other separate heater boxes and there are other choices for defrost.
By the time you put their A/C and the Heater in, you will have no room for passengers, just a dog on the seat.
