Do you know that feeling when we want to unlock the door, but unfortunately it is so dark outside that we can't get into the keyhole ? Or when we drop our cell phone and can not find it ? Such problems can be solved easily, but we must be adequately prepared for them. An excellent help in such situations are keychain flashlights. Of course, they will help greatly in other situations too where we need a light.
The size matters
What comes to your mind first when we say keychain flashlight ? Definitely that it shouldn´t be big. We know very well that size is relative and everyone imagines a small flashlight a little differently. However, it is the size that makes it the keychain flashlight. An indicator could be 5-7 centimetres. After that, keychain flashlight becomes keys on flashlight. Hand in hand with size comes power source, which is usually battery. With smaller flashlights, AA or AAA batteries are not really common. Much better option is CR123 type battery, which is more expensive but offers better properties. We are still talking about standard types of keychain flashlights, but the market can offer other possibilities that are even smaller and more compact.
A small emergency solution indeed
Yes, we are talking about micro-lights which serve to illuminate the keyhole rather than as a primary light source. Depending on the design, such micro-lights have size of a coin. We have certainly realized that such lights can not be powered by a standard battery, but they use lithium batteries of different types. Of course these batteries can not provide such comfort and properties, but everything is compensated by small size. Speaking of properties, we should mention type of bulb that these small flashlight use.
The answer has three letters
Today, the designers of the companies that produce flashlights use nothing but LEDs. Our selection should also go in this direction. The LED provides enough light with low energy demands, which is ideal for a small flashlight. Don´t worry about insufficient luminous flux, modern ultra bright LEDs can produce hundreds of lumens while being compact. Such gadget, however, comes with a higher price tag and that is why the ultra bright LEDS are only used in larger keychain flashlights.
What's not to forget?
We should not forget the basic – how do we attach it ? Keychain flashlights must feature some kind of attachment (opening on the tail and/or key ring, etc.) which allows convenient attachment to our keys . That really is a must. The material should be durable and that is why the aircraft grade aluminium or rubber (for those smaller ones) is used. Once again, it is up to us whether we opt for smaller or larger version.