Nightzone handlebar end lights

Richard said:

I'm thinking of getting a pair for my hybrid. But, it sez on the info,
"Not to be used with bar ends". Why not? They just look like they
plug into the handlebar end, and my bar ends clamp around the end as well.

R.

If they are the things I bought from Halfords they are [censored]. Althought
they work in a fashion, the build quality is so bad getting them out of
the wrapping will render them inoperable. Machining an alloy case for
them would be a good idea.

Richard said:

I'm thinking of getting a pair for my hybrid. But, it sez on the
info, "Not to be used with bar ends". Why not? They just look like
they plug into the handlebar end, and my bar ends clamp around the end as
well.
R.

Could it be that having forward facing red lights is illegal (I think?), and
the manufacturers don't want to take the chance that someone sticks them in
the end of bar ends?