If you have an old stove you can pipe it to make it a training prop for extinguisher classes, do not have any pics but with some modifications to the stove you can make it work. Use a small propane tank with a regulator from a gas grill.

this is one of the props that we have at our station that tests the skills of the firefighters with confined space as well as obstructions that they may encounter while going through them as well. The two rods that are in the prop are adjustable with the holes that are in the side to make the difficulty easier or harder at the ease of moving them closer or farther apart depending on the experience of the firefighter or the type of training you want to do. This prop can also be used without the obstruction bars as means of getting your firefighters down on their hands and knees in order to go through it. The prop opening is 3' x 3' and 8' long. It can also be easily adjusted to make your size constraints if need be.

Check out tes2training.com. Tim Sendlebach has some wonderful training props on his site. He provides material lists and dimensions, we have built several props and the guys on the department love them.