Fat Gripz Sleeve

I've just found out about these things. They seem interesting so I thought I'd get your guys opinion on them.

I really want to start thick bar training but I don't have the money for both a think barbell and thick dumbbells and this seems like a good money saving alternative for now.

How do they go on the bar? It looks like there is a slit in them so do you just open them up a bit and put them over the bar?

How are they for slipping around on the bar?

How big of a bar will they go on? Just a standard bar? Also, how big do they make the bar?

What do you think about them? The pros and cons?

Thanks

I've got some, MarkR is selling a pair now as well, I like them better than other products for the same problem. I don't use them every session, but they make a change. They fit better on my olympic dbs and my chinup bar than they do my olympic bar, the olympic bar is fatter, so it leaves a slight gap between the two sides when its on, doesnt bother me as i use my axle anyway. They are made of a very solid rubber, and hold tight to the bar, so there is no movement, i think they are 2 1/8 or 2 1/4 inches thick. They are a good budget idea if you dont want to buy thick handled dbs, or different thick handled attachments for accessory work, though they have a different feel to thick metal dbs. probably worth the money if you want a change every once in a while.