So we essentially shorten this 18 carbon molecule to a twelve carbon molecule to form a CIS delta three enol coenzyme A. Now notice we basically come to the same exact position as we were in this particular case. So here this acyl coenzyme A dehydrogenase cannot act on this molecule because of the presence of a double bond between carbon three and carbon four, as we saw in this case. And so once again, this same isomerase has to act on this molecule to basically change the position and the location. So the position and the configuration of this double bond. So we go from a sith double bond between carbon three and carbon four to a trans double bond between carbon two and carbon three.