Marching percussion instruments are instruments specially designed to be played while moving. This is achieved by attaching the drum(s) to a special harness (also called a carrier or rack) worn by the drummer, although not all marching bands use such harnesses and instead use traditional baldrics to sling their drums (the British Armed Forces, for instance, still use the old style of slung drums). The drums are designed and tuned for maximum articulation and projection of sound, as marching activities are almost always outdoors or in large interior spaces. These instruments are used by marching bands, corps of drums, drum and bugle corps, fanfare bands, indoor percussion ensembles, and pipe bands. A marching percussion ensemble is frequently known as a "drumline" or "battery." Breakdown Drumline A "drumline," also known as the "battery," or "batterie," is a section of percussion instruments usually played as part of a musical marching ensemble. A drumline can also be a section on their own competing against other drumlines. Marching bands, drum and bugle corps, and indoor percussion ensembles are some examples of groups that include a drumline. The battery marches on the field in a group as opposed to the stationary front ensemble. The battery usually consists of snare drums, bass drums, tenor drums, and cymbals. In the past, marching timpani were common, as were marching keyboard percussion instruments such as glockenspiels and xylophones. However, due to the addition of the front ensemble, all pitched percussion instruments have since been grounded. A relatively small number of bands, mostly at the collegiate level, continue to field such traditional marching keyboard instruments; however, most bands have phased out their use. Snare drums Marching snare drums have high-tension heads made out of Kevlar or PET film. In the past, snares were typically carried with slings. Slings caused the drums to tilt right causing discomfort in the left hand. Due to this discomfort, traditional grip was created. Most modern snare drums have rigid over-the-shoulder harnesses that hold the drum with the playing surface parallel to the ground, which affords the option of performing with matched grip. Even with the option of performing matched grip, most competitive groups opt to use traditional grip. Traditional grip allows for more exciting visuals or tricks which are important in the competitive drumming world. The center, or head, snare player (a position typically held by the most experienced snare drummer) is usually the ensemble's