I got these from my Local Beauty Supply Store and I must say that I love them only because they are so gentle on my hair.
However, they are very difficult to open and close, in fact, in the process of trying to open them, the "snapping part" (I honestly don't know what else to call it), disengages from the rolling part. It can however, be put back together. The reason I bought them is because I wanted something that would be gentle on my hair. They are also very comfortable to sleep in. They are inexpensive. I paid about 2 bucks for 12 rollers. These are 7/8 inch sized rollers.