Is it safe?

Hello Reddit! I recently purchased a great enclosure for the bearded dragon I'm planning on getting. I got it off craigslist for 75$ and it included a heat lamp and this pad on the side of the tank made by zoomed. The guy I bought it from says it will help keep my lizard warm. Its attached on the outside of the tank on the side. What I'm wondering is whether or not this pad is safe for both my bearded dragon and safe to use, eg is it flammable, risk of fire. I still have a lot more I have to purchase I know, and I want to be sure this pad is a good thing for my beardie. Please let me know, thank you. If you would like a picture of it, I could take one but be warned quality will be shot.