As a crime, it may not deserve comparison to the meticulously planned hotel heists of past decades, when well-dressed robbers cleaned out safe deposit boxes of jewels and cash. Yet the sheer brazenness of two jewel thieves at the Four Seasons Hotel on Saturday set their crime apart from the run-of-the-mill hotel larceny. When the two young men walked into the lobby of the hotel, on East 57th Street, it was nearly 2 a.m., a time when the staff makes a habit of questioning visitors as they enter, a hotel spokeswoman said. While one of the men spoke with the staff, the other man, wearing a tan trench coat and wielding a sledgehammer, smashed a jewelry display case near the concierge desk across the lobby, the Police Department's chief spokesman, Paul J. Browne, said. The thief grabbed a few pieces of jewelry, including wristwatches and a pendant and chain, Mr. Browne said. He said the jewelry was valued at $166,950. Although there were several jewelry display cases on the lobby floor, the one that the thieves sought out was full of pieces from Jacob & Company, whose owner, Jacob Arabo, has been called the Harry Winston of the hip-hop world.Mr. Arabo said in a telephone interview that the hammer-wielding thief had seized only a fraction of the jewelry in the display case because he was able to break only a small hole in it, limiting his ability to reach most of the jewelry. Although the thief removed three watches, Mr. Arabo said, he dropped one while fleeing. "This is small-time, running into a hotel, smashing things with a hammer," Mr. Arabo said. "Unfortunately, it happened to me. How come it was my window, when there were other windows with jewelry in the hotel?"Mr. Arabo said the answer to that question probably had something to do with brand recognition. "I think they would recognize my name more than anyone else's, from the magazines," said Mr. Arabo, who has been mentioned in songs by Kanye West and 50 Cent and served a prison term for lying to federal agents and falsifying records. The robbery was first reported in The New York Post, which put the value of the missing jewelry at $2 million. Late Sunday night, the Police Department released surveillance photographs of two men that it said were the suspects. Another jeweler, Gabriel Jacobs, who rents a display case in the Four Seasons, said he had thought the lobby was not a likely target for jewelry heists. "You don't think about this happening because it's such a high-end hotel," Mr. Jacobs, who is an owner of Rafaello & Company on West 47th Street, said on Sunday. Mr. Jacobs added that the hotel had always assured him of its security, telling him the case he rented could be opened only by a single special key - his own. He took further comfort that the case was made of shatterproof glass and hung well inside the lobby, not at street level. "We spend a lot of money to rent the space out," he said. "How could someone come in there and do that? That's just ridiculous."Indeed, Mr. Arabo said that he was now considering putting such displays behind bulletproof glass, standard practice for display cases at street level, but not for interior display cases, like those in hotel lobbies. Bulletproof glass, however, is hardly a guarantee against theft. At R. S. Durant, a jewelry store on Madison Avenue, for example, Sam Kassin, the owner, said he felt comfortable leaving products in display cases overnight because of the bulletproof windows and door - until last summer, when thieves smashed the door so many times that it came off at the hinges.Besides, said Joseph Krady, the owner of Madison Jewelers, "anything will shatter if you hit it with a sledgehammer.