One Step conversion from any Incandescent or Xenon bulb, screw-in, flanged or pin base.
Additional commercial models are avail for $20-$99 and up. Some of these put out 5-10 watts of light from LED's!
Custom models have over 10,000 Lux of output with 3v-6v batteries in series with fully regulated power supplies! But these are expensive...
MY Instructable uses FREE sample LED's and original base & components, fully reversible and backwards compatible!
see those other expensive mods at http://www.flashlightreviews.com/mods/mods_index.htm