The Flex Belt is an interesting product. Basically you have a belt that has gel pads in it. The belt actually uses EMS signals and causes you to tighten and tone your abs! This is kind of interesting to me. There are different exercises you do and these are supposed to help tighten your stomach. You will use this for 30 minutes 5 days a week. The GelPads are supposed to last for 30 uses so you will have to purchase more in the future, but it is definitely worth it for some people. I have not personally seen the results from this but people are really liking it from the reviews I have seen.
So, if you are looking for a new fitness product, check this out. I think it would be a big help for those who need tighter and toned abs. This site has a lot of answers to your questions. You may just end up buying one:)
I have not purchased from this site. All thoughts are 100% mine.