Ann Delmarmo, an entrepreneur and single mother, is standing in Pier 92, the massive event space playing host to this year's Small Business Expo in New York City. She is among the hopefuls lined up to speak with casting directors for Shark Tank, the ABC reality TV show in which entrepreneurs pitch their business concepts to angel investors.

"I feel that I could set off a feeding frenzy," says Delmarmo, eyes laser-focused.

Although it wasn't an official casting call, two casting directors listened to pitches at the Shark Tank booth, taking notes and on the lookout for potential talent. It was a popular attraction. By noon on Thursday, a long line of hopefuls clutching papers and props for their pitches stretched out in front of the booth. One woman earlier in the day brought Tupperware containers filled with her company's gluten-free baked goods.  

"We're looking for businesses in all stages of development," says casting director Emily Eldridge. "Everything from multimillion-dollar companies to brand new products."

So what makes a good pitch for Shark Tank? If you can condense your vision and the unique value of your product, along with supporting facts and figures, into a passionate 30- to 60-second presentation, that's a great pitch, Eldridge says. On the other hand, you can be too confident. When one hopeful said she would be asking the Sharks for a whopping $2 million, Eldridge balked.

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During Delmarmo's pitch, she planted her hands on the table and leaned in close to present her product: vibrant, reusable cotton napkins she calls "eco-kins" that are handmade in the United States from sturdy fabric. She showed Eldridge samples of the six-inch-by-six-inch napkins, which are intended primarily for use by schoolchildren. A mother of two boys, ages 6 and 9, Delmarmo got the idea for her product while packing school lunches. She sells the napkins in packs of two for $10 and packs of eight for $35.

Delmarmo says she would ask the Sharks for $100,000 in exchange for a 10-percent equity stake. Her goal would be to sell online first, and then later to break into small retail stores and upscale boutiques. Currently, she is selling directly to schools, which she started doing last month. Her entrepreneurial drive comes partly from her desire to be able to work from home and be there for her boys. "They're only young for so long," she says.

Paul Ackel is another small-business owner who pitched to the casting directors. Two years ago he founded Ampridge, a company that makes cable adaptors for Apple products. His niche: adaptors that let you plug a real guitar or microphone into your iPhone or iPad to play music on apps such as Garage Band, which is a virtual recording studio. As Ackel tells it, his products are the first such adaptors that don't contain active electronics. That means they don't drain energy from batteries or the Apple device, and they don't interfere with the quality of sound from the guitar or microphone.

"There are so many musicians; there are so many people with Apple devices," Ackel says. "All you really need to do is let people know that this exists and you have a huge potential market."

Ackel, who previously worked as a salesman for companies that serve the music industry, says few people are aware of his product. Ampridge made about $25,000 in sales last year. He says he would ask the Sharks for between $100,000 and $150,000 in exchange for 30 percent of his business. While Delmarmo seeks money to ramp up her production and break into retail stores, Ackel says he would use much of the investment to hire a full-time head of marketing, whose responsibilities would include social media outreach.

The Shark Tank casting directors told Delmarmo, Ackel and the other entrepreneurs that they would be in touch by the end of next week -- but only if the hopefuls were moving on to the next round of casting.

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