Powerriser, poweriser or powerizer?

So, what is the correct spelling of those spring-loaded stilts? Is it ‘powerriser’, ‘powerizer’ or ‘poweriser’? And what is the plural form of that word?

Many thanks,
Torsten[YSaerTTEW443543]

TOEIC short conversations: Employee is being briefed on how to get travel costs reimbursed.[YSaerTTEW443543]

Poweriser/powerisers, according to this link:
powerizerz.com/

These things look like accidents waiting to happen…

powerizer

powerizer.co.uk/

in.youtube.com/watch?v=GVTLHsuoBls

video.google.com/videoplay?docid … 5025322688

poweriser

Some of the differences between these brands and the genuine poweriser brand are price and type of spring. Poweriser springs tend to break down slowly over time by creating little cracks within the fiberglass spring. Powerskip springs stay stronger for a longer period of time, but when they eventually break down the spring usually cracks in half, rendering it useless. Other differences are the quality of manufacture and quality of components, where the more expensive brands, Powerskip and Poweriser, and to a lesser degree 7league boots have noticeably longer lifespans on all parts.

answers.com/powerizer

originalpoweriser.co.uk/

Other names are Flyjumper powerskip skyrunner

hotfrog.in/Companies/Flyjump … eme-sports

Hi Hank, what makes you think those powerisers are so dangerous? I mean there are other types of extreme sport that might be much more dangerous than that…[YSaerTTEW443543]

TOEIC short conversations: An employee ask her co-worker for small change[YSaerTTEW443543]

Ha ha. Torsten… I was thinking about my brittle bones strapped to those things. I’m no spring chicken, you know :).

Hi Hank, how do you know your bones are brittle? They might be as elastic and bouncy as the springs in those powerrides ;-).

By the way, what exactly is a ‘spring chicken’?[YSaerTTEW443543]

TOEIC short conversations: An employee asks his co-worker to help him with the photo copier[YSaerTTEW443543]

spring chicken = Cornish game hen I think. I looked it up:
wisegeek.com/what-is-a-spring-chicken.htm