You may be thinking of the Enerjoy Panels carried by The Bean Farm. I believe their prices are very good compared to other carriers of the Enerjoys.
There is also Pro-Products (the best, IMO). You can only get their panels direct from them, I believe.
Then there is Helix Controls
From cheapest to most expensive, it's Enerjoys, Helix, and Pro-Products.
There is one other heating device sold as a heat panel for reptiles, but I don't even care to mention it. The reason why true RHP's work is because of a reflective layer and a strategically placed air space. Anything without those two things is no different than placing flexwatt on the ceiling of your enclosure.