Stigma (letter) Stigma (letter) Stigma (ϛ) is a ligature of the Greek letters sigma (Σ) and tau (Τ), which was used in writing Greek between the Middle Ages and the 19th century. It is also used as a numeral symbol for the number 6. In this unrelated function, it is a continuation of the old letter digamma (originally Ϝ, cursive form ), which had served as a numeral since antiquity and was conflated with the σ-τ ligature in the minuscule handwriting of the Middle Ages. The στ ligature (, ) was one of many ligature forms that came into widespread use as
Torque tube of the drive shaft and tunnel." The continuing limited production of the Avanti switched to a new chassis in 1986 that utilized a torque tube along with an independent rear suspension. The Mercedes SLS has a torque tube, but only to align the transaxle with the engine. Sine 1998 the Chevrolet Corvette from General Motors has used a torque tube since the introduction of the C5 version in 1996. Torque tube A torque tube system is a drive shaft technology, often used in automobiles with a front engine and rear drive. The torque tube consists of a large diameter stationary