I just got HALF of the answer to my own question.---I was able to weigh the F75 stock coil today on my very accurate scales and it weighs 17oz.--To put this in a perspective (of sorts), the new 11" Pro lightweight coil for the Explorer weighs 19oz (which has helped somewhat with the weight and tremendously with the balance) of the Explorer.--So, the F75 with a 17oz coil out on the end of the "stick" (and especially of those measurements, and a DD)-is speaking very well for the F75. I am getting an F70 in a few days and I can post at that time the weight of that coil-if anybody is interested.--It will, of course be some lighter due to it's physically size AND being concentric.---I just wondered if the weight difference in those two machines was entirely (or almost entirely) in the weight of the coils.--There is detector weight and then there is detector weight!---The weight (and size) of the coil out on the end of that shaft can SURE make a difference.-------Del