Why is my cord so weird

[Cam]

I bought my icecap MH 175 from this guy in calgary supposedly new, and got home and realized that i have funky three prong end on my cord for the ballast. I don't think its for 220 volt because thats usually just two prongs isn't it. Does this mean that i have 277 volt and if so is it true that my ballast is basically useless because a converter for this type of power would be more than what i paid for the ballast. Any suggestions or ideas about what this cord actually is would be helpful.
thanks
Cam

[Pescador]

The cords from my Hamilton pendants have the same ends where they plug into the ballasts. I'm guessing it's so you don't plug the wrong end into the wall.

[Tarolisol]

Is it the plug my the light to the ballast or the ballast to the wall/? Plus most plugs that have anything to do with water have three prongs two flat one round its the ground.

[Cam]

A lot of plugs have a third prong as a ground true but this plug has three prongs that aren't shaped normal. In other words i can't plug this ballast cord into the wall it's shaped different. My light is just wired to the ballast no plugs to clarify.

[Beermaster]

Pictures are worth a thousand words

[Tarolisol]

strange, pictures would be great.
Does it look like this
http://www.vapodepot.com/assets/plug-220v.jpg
or this
http://www.fuzing.com/members/2/77/00041277/53258.300x300.jpg