Just to share my experience with the plastic drawers.
I personally did not like them. I had heat tape on the bottom of them and it was almost impossible to shut them. I think I used mine for 3 weeks until I went ahead and bought a shelf kit at a home improvement store. It has worked out great and I can get to my animals a lot quicker and easier. Seems to be less of a chore.
If you must work with the drawers, you can get heat tape and a thermostat at beanfarm.com. They seem to have pretty good prices and have everything that you need.
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