Nonanoic-6,6,7,7-d4 Acid (CAS# 1219795-27-3) is the labelled version of n-Nonanoic Acid (N649385(P)), which is commonly used in conjunction with glyphosate, a non-selective herbicide, for a quick burn-down effect in the control of weeds in turfgrass. It is also used in the preparation of plasticizers and lacquers.