Mechanical pencil

A typical construction of a ratchet-based mechanical pencil. A mechanical pencil, also clutch pencil, is a pencil with a replaceable and mechanically extendable solid pigment core called a "lead". The lead, often made of graphite, is not bonded to the outer casing, and can be mechanically extended as its point is worn away as it is being used. The vast majority of mechanical pencils have erasers.
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