Advancedmart 0.5 Watt Keychain (LED-005S)

Light Type: 8mm 0.5W LED
Light Class: Pocket / Keychain

The Advancedmart 0.5 Watt Keychain (LED-005S) is a really cute little keychain/pocket light that really performs well. It has a silver finish, is knurled for grip, and has a clickie switch on the tailcap. The Security Quality LED is one of the newer 8mm 0.5 Watt LEDs and inside is a boost circuit to drive the Security Quality LED for many hours on a single AA cell.

The body is made of anodized aluminum with a silver finish. Near the head are 3 decorative rings machined in the aluminum followed by a wide band of knurling which is only slightly aggressive and provides a very good grip. Another ring of knurling surrounds the tailcap for ease of removal when it comes time for a battery change (not too often!) The tailcap has a drilled tab for the keychain attachment (included) and has a domed clickie in the center of the tailcap.

At the front of the light you will find a recessed plastic lens with the 8mm 0.5 Watt Security Quality LED inside a smooth reflector. Despite the use of a smooth reflector, the beam is quite nice. Inside the head of the light is a DC-DC boost circuit to power the Security Quality LED with the single AA cell in the body tube. The circuit also regulates output to some degree, keeping the light from simply dropping off as it normally would without the circuit.

Output is in the form of a bluish tinted beam which has a distinct wide central spot surrounded by a distinct corona. Only very slight imperfections in the beam were found. This particular 8mm Security Quality LED was a bit less purple than many of the 8mm LEDs I’ve reviewed so far.


Beam at one meter at target center.

Runtime Plot: Well, I can tell you that this one surprised me a bit. 6 hours to 50% was more than I was expecting. After about 8½ hours output drops off completely as the boost circuit can no longer draw current from the now dead battery.


Runtime completed with included “Tianqiu” alkaline AA battery.

Runtime Plot: Special request. Energizer L91 AA lithium cell: more output and steadier output.


Runtime completed with “Energizer” lithium AA battery.

The switch is domed so that it matches the contour of the tailcap. It is a reverse clickie – the light doesn’t come on until after the switch is clicked. Some people don’t like this setup, but in a pocket/keychain light it can be very beneficial. If the button is pressed by accident the light doesn’t come on unless it goes all the way in and clicks. This helps prevent accidental draining of the battery while packed or in the pocket. Pressing the light’s tailcap on a flat surface until the switch is flush with the opening in which it sits does not turn on the light. Activation can only happen if the switch is pressed in beyond the end of the tailcap, thereby reducing accidental activation even more.

The light has an O-ring seal on the tailcap, but it is not well lubricated. You may want to throw a little silicone grease on the ring to help keep it in good condition. As for water resistance, I’m not too sure about the tailcap switch, but I’d say it’s splashable at a minimum.

Ergonomics: It’s a bit big for a keychain light, but it is very lightweight. The knurling provides good grip and the clickie is easy to activate with the pad of my thumb. No real issues here.


Size compared to a common 2AA aluminum light

A single AA alkaline cell powers the light. To change the battery simply unscrew the tailcap and drop out the old cell. Place a new one in positive first and reattach the tailcap.

A keychain attachment is included and attached to the light.

What I Liked: Water resistant, Tough/impact resistant, Long battery life, Good output, Easy battery change, Lightweight

What I Didn’t Like: Not much at all.

Other Things I Noticed: Whitest beam of the 0.5 Watt LEDs I’ve seen yet.

Conclusions: Fantastic little keychain/pocket light. The long runtime could come in very useful in many situations. If you are a fan of the Infinity Ultra, you’ll probably take a liking to this one as well.