Pencil sharpener pencil in position, although they then sharpen them to the usual conical point as for a round pencil, abandoning some distinctive aspects of the carpenter's pencil. Sharpeners with a single blade for use on wax crayons are available, and sometimes included in boxes of crayons. These often have plastic blades, which are adequate for the soft wax. Mechanical pencils dispense the graphite lead progressively during use and thus do not require sharpening; such pencils are sometimes called "self-sharpening". A type of mechanical pencil has a rotating gear mechanism which rotates the lead slightly every time the lead is lifted off
Lead single Lead single A lead single is usually the first single to be released from a studio album, by a musician or a band, before the album itself is released. During the era of the phonograph record, all music arrived in the marketplace as what is now termed a single, one potential hit song backed by an additional song of generally less commercial appeal on a single ten-inch 78 rpm shellac record. After the launch of the long-playing microgroove record in 1948 and the arrival of the 45 rpm single the following year, singles continued to appear separately from albums into