The LED flashlights sold on this site are high-performance precision tools. Like any precision tool, they need to be handled and used properly to ensure the safety of you and your surroundings.
The flashlights can get hot to the touch if left on for extended periods of time. Never leave the flashlights on unattended, and never leave them where children can gain access to them. In particular, the Dereelight C2H 4SD and MC-E versions of the Dereelight DBS become hot very quickly. Do not operate the aforementioned flashlights in the high mode for more than 10 minutes at a time. At that time you should allow them to cool by switching to a lower mode or turn them off.
The beams these flashlights produce are very bright! Do not shine any of these flashlights in your eyes, or the eyes of others. DO NOT leave them unattended where children can access them, they can cause eye damage to themselves or others, or possibly burn themselves.
The lithium batteries that these flashlights use also deserve special attention. Do not store the flashlights in environments that can become exceedingly hot... a car interior in the summer for instance. The batteries can become too hot, and may pose a fire hazard.
Do not mix different brands of batteries. Do not install batteries that have differing states of charge into the same flashlight.
When charging rechargeable lithium-ion batteries (RCR123, 18650 Li-Ion, etc.), ALWAYS place the charger on a fire-proof surface, away from any combustible items that can ignite. Chargers of all brands have been known to fail, and can overcharge the batteries causing them to explode or vent rapidly with flame. NEVER charge them unattended or overnight... you need to monitor them in case something goes wrong.
NEVER attempt to charge non-rechargeable lithium batteries (CR123a, CR123, etc.), they can explode or catch fire.
Use only chargers designed to charge lithium based batteries, and of the correct output voltage for the battery/batteries being charged.
Always store lithium based batteries in a fire-proof area or container. Do not transport them loose, they should be in a carrier that will prevent them from contacting any metallic objects that can cause them to short-circuit. (Not in pants pockets with coins or other metal objects). If short-circuited, the batteries can become extremely hot or catch fire, or even explode.
When using rechargeable lithium batteries (Lithium Ion, known as Li-Ion), use only the protected varieties. Protected batteries have a small circuit added to them that will shut down the batteries if certain dangerous conditions are sensed. These conditions are over-charge, over-discharge, over-current, low-voltage, and short-circuit. Any of these conditions can cause a lithium battery to vent rapidly with flame, explode, or catch fire. For this reason, protected batteries are a wise investment.