If it is for the convenience of carrying every day, small size and lightweight is the first consideration.
As an emergency lighting product, brightness is an important factor to measure the user experience of an excellent lighting product. Lumens (lm) is a measurement unit of luminous flux, designed to calculate the total light energy produced by a light source per unit of time. It can only explain the strength of light energy and has nothing to do with distance.
Since it is an emergency item with you, if the battery cannot be easily obtained, its function will be greatly reduced. Therefore, AA flashlights must be compatible with a variety of batteries (alkaline batteries, lithium iron phosphate, rechargeable 14500 lithium batteries), in order to be at the critical moment Don’t drop the chain. You can also choose a flashlight that can be recharged, especially some flashlights that can also be used as an emergency power bank to output electricity. Such as this one https://www.olightstore.de/olight-marauder-2-desert-tan-taschenlampe.html.
Friends who play outdoors know that in addition to brightness, a certain range is required to ensure the visible distance outdoors, which is also convenient for surveying remote path conditions.
There are many uncontrollable factors in the outdoor environment, and it may be caused by a sudden heavy rain or accidentally falling into the water. Therefore, the waterproof capability of IPX-8 is also a necessary feature for carrying EDC with you.