Every thing Beach hunter said about the "ID" is spot on. I would though emphasize that rebalancing as you move along from one ground environment to another is critical for optimum depth. The manual is quite specific with instructions on how to do it. I use mine in fresh water continue up the beach, parking lot, and fields. It works anywhere, just keep ground balancing it, just takes a couple seconds. It is sort of second nature with me, like checking the rear view mirror. I would add, this is a well balanced machine. The weight is supported by your shoulder and not your forearm, so you can get 2 to 3 hours of hunting without constantly switching sides..You also have the option of hip mounting the box, but beware of snagging the headset cable. As far as the light system go'es, its a 3 tone detector. I never look at the lights unless it nulls. The light may still show you what's there.
Here in Florida, we get rain almost every day in the summer. You can detect right through it, no covers or anything else to protect it. I also recommend disassembling the shaft occasionaly, cleaning it and putting on a quick spray of silicon....HH Gil