The official global site of camera & lens manufacturing company sigma.here you can find information about our company and our products, support, repairs and inspections, as well as news, updates,.. The greek letter σ (sigma) is used in statistics to represent the standard deviation of a population.
It also has various uses in other areas of math and science.. Sigma supplies a full range of global and domestic water and wastewater products including fittings, restraints and extended range products along with castings, fabrications and custom parts for oem.