military and orchestral percussion instrument having several gut, nylon, wire, or wire-covered silk strings (snares) stretched across the lower, or snare, head; the snares vibrate sympathetically with the lower head (to which vibration is transmitted from the upper, or batter, head by air vibrations inside the drum), causing a snappy, penetrating, relatively high-pitched sound. The modern snare drum has a cylindrical shell of wood, plywood, or metal 5-12 inches (13-30 cm) high and 14-16 inches (35-40 cm) in diameter; deeper models, called field or guard's pattern drums, are used in many military bands. The heads, beaten with two tapered sticks ending in small knobs of wood or nylon, are of calfskin or plastic. They are held in place by a flesh hoop (around which the membrane is lapped) and a counterhoop. Membrane tensioning is by screws that act independently on each head, by metal rods, or, now chiefly in military bands, by rope lacings.