Believe it or not, some stocks can even stump Jim Cramer.
When that happens, he puts it on his list to do more homework, and then follows up with investors to make sure that they receive a reasoned response. Sometimes, the research is surprising.
Cramer first vowed to do more research when an investor on "Mad Money" asked about Tetra Tech.
Tetra Tech provides consulting and engineering services for companies and governments handling complex problems with water, the environment, energy, infrastructure and resource management.
The company doesn't build anything. Instead, it does all the things that need to happen before building, like data analytics, assessment and planning. Tetra has made various acquisitions to expand overseas and provide more exposure to government customers, like the EPA.
"Basically, Tetra Tech has become a play on the rise of environmental regulation worldwide," the "Mad Money" host said.
Cramer had two concerns about the stock, thanks to the new Trump administration. First, the upside could be baked into the stock already because it has run 66 percent for the year.
Cramer's other fear is that Tetra Tech may not be the best way to play the Trump administration. While Tetra could benefit from infrastructure spending in the next decade, Trump also is a believer in deregulation, Cramer said.
Especially when it comes to the environment.
That could translate into less demand for some of Tetra's services, particularly since the company gets approximately 25 percent of its sales from the Federal Government,
"I think the future is too murky to own Tetra Tech up here, particularly when you consider how much the stock has run. If you own it, I'd say ring the register, at least until it pulls back to lower levels," Cramer said.
The next stock that Cramer researched was AdvanSix, the resins and chemicals business of Honeywell that spun off at the beginning of October.
The company is the leading manufacturer of Nylon 6, which is used in many items ranging from fishing nets to plastics and industrial packaging. However, Honeywell has been trimming its portfolio to focus on the high-growth and high-margin businesses. AdvanSix is neither, Cramer said, which is why it was spun off.
Unfortunately, the business is facing increasing competition from the Chinese.
"I think these guys have their work cut out for them. I like Honeywell a great deal and I think that its value was enhanced by the spinoff of AdvanSix. No need to trifle with this one, stick with Honeywell," Cramer said.
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