Here are search results for "heat tapes"
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It's gorgeous! And worth quite a bit too
That's a beautiful example of the lamp. In what looks like excellent condition, it's likely worth $400-$500, depending on the auction and how you market it.
I have four of these lamps myself in red, green, blue, and gold. I adore them!
Yes, hold onto it! Nothing is known about Heat Tapes. Inc. save that Lava once sued them-- probably over their other model, the Bubble Lite (a knock-off lava lamp). These are very uncommon, especially in colors other than red, blue, green and yellow.