^ in the winter months in particular, and sometimes in the summer when out at night, I will carry a cheapo AA flashlight like this
https://www.amazon.com/gp/aw/d/B00IEMUOWU/
https://www.amazon.com/gp/aw/d/B00CEOII9K/
Both are blinding up close. The first one is dimmer and doesn't have a bezel front, but it turns on upon partial push of the button. Second needs to be "clicked" before it lights up, but it is a good deal brighter. A bezel may be useful in self defense, but you'd be holding a few ounces of metal in your hand either way. I carry the first one (without a bezel) if I'm likely to get screened, it's not as threatening, and therefore less likely to be taken away.
The second one has multiple modes (high, low, strobe) but I would look for one without those.
They both have zoom lenses so you can focus on something in the distance or shine it under your feet. And they're cheap enough to buy a bunch and leave around the house and in your car.
Keep in mind, brightness and battery life are inversely related. If you use it rarely, might as well make it bright as you can go for the size you carry, otherwise you might want something with a dim mode as an option.
Also, most Amazon sellers are full of shit about how many lumens their flashlights put out. Some of them are just more subtle about it (overstate by 10-20% instead of 300-500%). Read the details and reviews. You can always Google the bulb model for the truth.
Same as with CCW, the smaller it is, the more likely you are to bring it with you. You can also find AAA lights in a similar budget range, they will be smaller but emit less light. I used to have a cheapo Duracell AAA - light enough to keep on my keychain for finding my keyhole at night, but it wasn't going to blind anyone in the dark.
I think this will be my next buy for the AAA size:
https://www.amazon.com/gp/aw/d/B01FCTFZTO