Well, I am far from a Colt semi-auto expert, but there are Commander models, Combat Commander models, and Officer's models and "sub" models such as Concealed Carry Officer and General Officer's and so on. I believe one would need to know what series (70 or 80, for example) and the specific marking to answer your question accurately. Perhaps someone with more knowledge will attempt to help sort it out, but it sounds like, despite its sometimes value inaccuracies in the current Colt market and occasional errors simply because of the volume of data involved, you might benefit from a Blue Book of Gun Values by S. P.Fjeldstad or other reference book that might be recommended based on your specific area of interest. HTH /forums/images/graemlins/cool.gif