Anyone know where I can find this? The mech. inspector wants to see it because we have a 14-2 running horiz. through an apartment bedroom wall with an air transfer it it. The forced air HVAC system has a main return in the living room. And in the bedroom/hallway wall they have transter grilles for relief air. One is on the bedroom side close to the floor, and the other is in the hall near the ceiling. They just use the stud space LIKE a return. Usually they just put them straight through the wall down low, but the owner is worried about noise transfer, thus the different heights. If it has a flame spread rating of 5 or less it can stay according the the Mech. inspector. I argued that it wasn't an actual return just an air transfer. The romex is Southwire brand, and I've been all over their website and can't find anything. Any help would be great.