The mark consists of a bold font sigma symbol as commonly used in statistical analysis indicating deviation or statistical variation. The sigma symbol is encircled in a bold circle of approximately the same font width or boldness. The top right script tail of the sigma symbol moves to the right within the circle and connects to the circle encircling the sigma symbol creating a break within the inner, negative space between the sigma symbol as it sits within the bordering or encircling circle. To the left and right of the circle are wings of which the inner ends are not completely connected to the circle. The wings are evenly placed on either side of the circle. The left wing begins at approximately the 7 o clock position and ends at approximately the 10 o clock position. The right wing begins at approximately the 5 o clock position and ends at approximately the 2 o clock position. The wings are each composed of 4 feather-like arms which are nearly evenly spaced between each of the feather-like arms. The wing arms are progressive in length with the smallest arms originating at the lowest points along the circle and the longest arms originating at the highest points along the circle. The outer edges of each wing show a slight, outwardly bowed curvature with the top, exterior edge of each arm showing a slight upward point. The overall shape of each wing is oriented in both an upward and backward position similar to the transition of a bird's wings from the uppermost position in flight before beginning the downward motion to create lift. The word "PTERA", latin for wing (s) or winged, is placed in a centered position just above the sigma symbol and bordered by the longest, upper arms of each wing to the left and right. The word "PTERA" spans approximately 90% of the distance of the horizontal measurement of both wings. The word "PTERA" exists in all capital letters in an American, mid-century modern like font with even spacing between each letter of the word. The word "SIGMA" sits below the circle surrounding the sigma symbol and is centered between the lowest arms of each wing with approximately 90% of the word existing between the total horizontal measure of these arms.