floaties, flotation vests, swim sweaters, what for 1 & 2 yr olds?

I need help figuring out what swim gear I need for my toddlers. I'll be taking my 13-mo-old (non-walker) and 2.5-yr-old to the pool for the 1st time this summer.

I've seen floating rings, flotation vests, swim sweaters (inflatable ring on a shirt kind of thing), etc. out there. I've read some reviews on amazon but am confused about what is really safe for a 1 and 2 yr old? Any recommendations? I like the look of the flotation vests - nothing to inflate - but know nothing about them.

Oh -- I should say I just found this post after posting my question the first time (http://www.windsorpeak.com/dc/dcboar...ng_type=search) but would still appreciate any advice.

Also, both children are signed up for swim lessons in 2 weeks.

Thanks, Ruth