The kilonewton, symbol kN, is an SI unit of force. It is equal to 1000 newtons (N). Note that the unit symbol "kN" must be written with a small "k" and capital "N", but the unit name "kilonewton", like "newton", is all small letters.
It typically has six and a half octaves (46 or 47 strings), weighs about 80lb (36 kg), is approximately 6 ft (1.8 m) high, has a depth of 4 ft (1.2 m), and is 21.5 in (55 cm) wide at the bass end of the soundboard.
The notes range from three octaves below middle C (or the D above) to three and a half octaves above, usually ending on G. The tension of the strings on the sound board is roughly equal to a ton (10 kilonewtons).
The lowest strings are made of copper or steel-wound nylon, the middle strings of gut, and the highest of nylon.
The tonne may also be referred to by the strictly SI term megagram, symbol Mg.
Like grams and kilograms, tonnes have also given rise to a force unit of the same name: 1 tonne-force = 9.80665 kilonewtons (kN), a unit also often called simply "tonne" or "metric ton" without identifying it as a unit of force.
Note that it is only the tonne as a unit of mass which is accepted for use with SI; the tonne-force or metric ton-force is not acceptable for use with SI.