I have this old 2D flashlight , and I thought it time for a LED upgrade : 

So I got me a 3v LED replacement bulb off Ebay .. I mean how bad could it be ? 

I must admit this light is old , and some what corroded on the inside , so I was expecting ( not very much )

With fresh batteries I got some ( measured ) 110mA current , which equates to around 0.35 Watts  ..

In the light box , the best I could get was 55 Lumen ..  It was very difficult to get a steady current reading so please dont bother with the calculator ..

Now the package say's 150 Lumen , so I'm about 100 Lumen down ..  

This is a old light , so low current draw with usable amounts of output is a plus . 

The beam is not pretty if you can imagine , and a very nice RING is produced that grows quickly with distance ..

Now that I have tried it , would I recommend it ?

Actually No ..  

It works , but the design for use with 2D flashlights is very bad .. The emitter simply does not match a Crypton bulb , or any filament type bulb at all ( For transmitting light ) .

The old adage , something is better than nothing , comes to mind .

Looks to be reliable 

Outputs decent amount of light

Low current draw ( ? )

Fits all flashlights that take a Crypton bulb ( This style )   

Could it work in 3D / C  ( ? ) 

More pictures ASAP: