On CNBC’s “Mad Money Lightning Round,”Jim Cramer said Vertiv Holdings Co (NYSE:VRT) is “very good,” however: “I do prefer, because it was down today, that you buy the stock of Dover (NYSE:DOV).” When asked about Serve Robotics Inc. (NASDAQ:SERV), he said, “There’s a gigantic secondary coming on, a lot of insider stock going, and I don’t like that. I don’t like to see that, because the company’s losing a lot of money. So, I don’t want to be there.” The “Mad Money” host recommended buying Bank of Montreal (NYSE:BMO) right here. “I got to get to the bottom of Celsius (NASDAQ:CELH). I mean, this t…