no idea why the instruction sheet sez it's not supposed to work.
"if the black plastic piece from which you removed the bulb has two holes beside the holes where the bulb came out, you have an older flashlight. To use the NewBeam(tm) LED module, you need to purchase a new Mini Maglite(r)"
i'm guessing that the two plug in plastic "tabs" on the NB unit don't fit in
the remaining tube sleeve. i'll have to look later.
works like a charm though