At Kumbh Mela , the largest congregation on earth where all big marketers are vying to sell their wares and boost their brands, one promotion that stands out is Hindustan Unilever’s ‘Roti Reminder’ for its Lifebuoy soap brand, ET reports.The country's largest consumer products firm, along with creative agency Ogilvy , has partnered more than 100 dhabas and hotels at the mela site to serve rotis that are stamped with “Lifebuoy se haath dhoye kya?” (Have you washed your hand with Lifebuoy?) "The ‘Roti Reminder’ gets a consumer’s attention at the exact time when hand washing is critical,” Sudhir Sitapati, general manager, skin cleansing, at HUL , says. That is, right when she sits down to eat roti with her hand.The company has made special heat stamps to make an impression of its message on rotis and hired 100 promoters to stand in 100 kitchens across the mela. The campaign started on February 1 and will run for 30 days. The company hopes to put the hand wash reminder on 2.5 million rotis.“The Maha Kumbh provides a unique opportunity to communicate this message to a large, predominantly small-town and rural population,” Sitapati says. “In effect, this simple, clutter-breaking idea will help us reach out to a massive audience, at a fraction of the cost.”