The North American Industry Classification System (NAICS) is a numerical system that classifies business establishments by industry. This system is used by Federal statistical agencies for the purpose of collecting, analyzing, and publishing statistical data related to the U.S. business economy.nd although the NAICS code system is used more often today, the SIC system is still being used by some government bodies, including the Securities and Exchange Commission. NAICS industries are identified by a 6-digit code, in contrast to the 4-digit SIC code.
Trapezius Muscle. The trapezius is one of the major muscles of the back and is responsible for moving, rotating, and stabilizing the scapula (shoulder blade) and extending the head at the neck. It is a wide, flat, superficial muscle that covers most of the upper back and the posterior of the neck.
Trapezius muscle explained. 1  Part 1: Upper fibres of the cervical vertebrae. 2  Part 2: The area commonly known as upper trapz. 3  Part 3: The mid-portion of the Trapzius.  Part 4: The lower fibres of Trapezius.