What should I wear to the IET dinner?

More than likely Your husbands dinner will require him to wear his Cl A's. If he wears his Cl A uniform I would wear I a dress that compliments his uniform but at same time is not too revealing for that can also have adhverse action on him if your dress is to revealing. On the other side of that, If he is in ACU's for the event then i would go with something that is not to formal and not necessarliy casual. I would advise at least wearing a skirt. You should be able to contact the Unit he is in and they could give you a better answer. But from my experience with OUST places they are usually semi-formal