I have a Raine 012H. It can be worn horizontally or vertically.
If you look at the picture, you can see there is a piece of elastic over the head of the light. I found it unnecessary, and carefully cut it off.
Mostly I wore it horizontally, with a mini-mag, a Leatherman Supertool, and a brass pen I used to have (It was sweet, a Rotring, and stolen).
I ran down the flightline, worked in tight spaces snagging it on things, and hung upside down working, and it never ONCE fell out.
I got mine in a uniform shop in Lousyana for under $7, I don't know what the go for online though. It is sold as an EMT pouch, and behind everything, there is a slot big enough to put a pair of scissors.
There is a vertical version of it, that I think is cheaper, it's model # is 0012.
Raine website /ubbthreads/images/graemlins/thumbsup.gif