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
Cap torque tester Cap torque tester The cap torque tester is used in the packaging industry to measure the opening or closuring torque of the screwing cap. It is a piece of specific quality control equipment that can be placed on the production line or in the laboratory. A torque tester is required during the packaging design process. It can be used as a destructive tester to identify if there is any material weakness of the packaging during the screwing process. It also allows one to define the torque tolerances of the capping machine. The lower torque limit is considered the minimum pressure