[Marwan]

it zaps only if you touch it, but the chances are high if your buddy is close because the antenna is a bout a meter long. it sometimes zaps me if i make certain movements, but it does give you piece of mind.. but thats why i keep it off, so that we could enjoy the dive and if we do actually see a shark, switch it on... of course there could be instances where we will not be so loucky as to see it first... but like i said , in my area the chances arent that high