I bought 5 of these at least 8 years ago for walleye fishing. Use them on my heritage lakers, ht polars and jack traps, Just replaced the batteries two years ago. They are a gravity type switch(upside down off, right side up on). These are the original night stars. A larger company screwed this guy over these lights some how and took the name, but he's still makes them. Down side: there's no on/off switch (I use a pc of plastic to slip in between the battery and the connection. Might even come with a pc of plastic.) Don't think they are waterproof, but I have had mine out in terrible weather and they all still work. They attach to the flag by a pair of Orings (It works fine but a little hokey.) They are on the heavy side(but flags still go up)jack traps are a little slow and the light has to be set in just the right place. I have owned a few different lights including the imitation night stars, these are the only ones I would recommend to other fishermen and the only ones I would buy again.