- Click button on/off - not twist, and not hold. This is what they changed on the Energizer - you have to continually squeeze it now for the light to stay on, and that's very impractical.
- Small and light - ideally 3.5" length max, and slimmer is better.
- I prefer replaceable battery, but would consider rechargeable.
- Doesn't have to be super-bright - 15-20 lumens is fine. Brighter is ok, but not required. I keep a more powerful light in my pack, but this is just for a quick, convenient, "need to find the keyhole in the dark" kind of thing.
- Cheap - the Engergizer one was less than $10. That may not be possible now, but I'd like to stay around $20 or less if at all possible.