I've seen the question of whether to use a coil cover at all or not come up fairly often. As to general wear for many of us, we probably don't need one. However, I've also seen several posts where people have either actually slit a coil when hunting around rocks and a case or two where continual beach hunting where the sand wore a hole through the bottom. They can cause false signals if mineralized soil and moisture gets trapped, but that's not a problem if you're aware and clean them out now and then. I personally believe if you're not at least rubbing the ground lightly, you're losing depth so I use covers and have found no detriment to the depth or use of my detectors. My two bits.
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