Okay, the user wants me to translate "double-neck" into French. Let me think. The term "double-neck" is commonly used in music, especially for guitars. In French, the equivalent term is "double-cou". I need to make sure that's the correct translation. Let me check a few sources. Yes, "double-cou" is the standard term used for a guitar with two necks. Since the original content isn't in French, I should translate it. No explanations are needed, just the translation. Alright, the response should be "double-cou".