Yes the mounting is metal but, there is a space between the plastic mounting collars. Its a little square plug that fits in between the mounting collars of the transducer. I have a Helix 9 G2N also and I had one in my package also. I have mine mounted up front on the bow so I didn't use it. However I have two transducers on the transom. I installed the plugs in both as I would shoot a rooster tail sky high even with my little 50hp.