I don't know. The rings are easier to throw. Fashion statement?

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"j" ganz @@
www.sailnow.com

wrote in message
ps.com...
Can anyone tell me the advantages and disadvantages of a horse-shoe
lifebuoy over a ring shaped one? Why have they become so popular and at
the same time why are they not approved for commercial use in places
like Canada? What is the theory behind there shape?