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Rubbu Rolu is a traditional grinding stone especially for preparation of Idli, Dosa, Attu. A flat device, with a hole, wherein we have to put the wet dal and grind it with a horizontal stone piece by making rounds. The consistency and flavor of the batter is unmatched when compared with today's wet grinders. It is used for pulverizing various herbs such as ginger, garlic, cilantro, peppermint leaves, etc.