I have been using a double door stainless refigerator for about 10 years. Cut a damper hole on the bottom and put a 4 inch pipe and chimney cap woth a damper in it for a flue. I use a hot plate and a pan of charcoal for a heat source, and either hickory chunks or apple wood for smoke. I put an old cookie sheet on top of blocks above the charcoal to stop flare-ups. It is big, 4 feet wide and 2 feet deep inside, and Ive had 120 pounds of kolbassi in it. Probably wouldn't need charcoal if it was a single door fridge, hot plate would be enough heat.