Stigma (letter) sigma form ς never occurs inside a word and is never used as a numeral either. Uppercase forms of stigma as a numeral (Ϛ) are rare in practice; when they occur, they can often be confused with uppercase forms of another numeral symbol, koppa (Ϟϟ), which stands for 90. Stigma is encoded in Unicode as "Greek letter stigma" U+03DA (Ϛ) and "Greek small letter stigma" U+03DB (ϛ). 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
Torque screwdriver rotary motion. Drilling responds to the same description; general-purpose power tools ("drill/drivers") are designed for both screwdriving and drilling, with a slipping clutch and low speed added to the drilling functionality. In an industrial environment dedicated tools optimised for their particular function are more often used. Corded electric torque screwdrivers are commonly made in three different designs: pistol grip, angle and inline. This type is the one mostly used for industrial assembly applications such as electronic assembly and small parts assembly. Brushed electric motors and more efficient brushless motors are used. The torque ranges typically from 0.18 in lb (0.02Nm)