Pros: Bulb Durability, Battery Life, Durability, Brightness
Bright, tiny, durable
It is very waterproof for any reasonable use. Works several feet down. Good flood pattern, sufficient for map reading, key hole findind and guiding way down dark path. The only caution is that contact along the body between front and rear pieces will activate light (That's how screw activation lights work) such as resting on a key, carabiner or other metal object. Be careful of how it sits at rest. Best use is zipper pulls, plastic rings, etc. Just pay attention or you'll find a dead battery. That is the only reason I gave a four. But the performance is well worth the concern. Batteries last a long time, if you're careful of this.