Great purchase. [SEP] These work with or without products.  I have used them on damp hair, and completely dry.  They do not include directions so you have to go online and watch videos on how to use them properly.  The way you hook your hair will depend on if it goes in to the curler properly.  These are not comfortable to sleep in.  Also sleeping in them does not affect the outcome of the curls.  They are very springy.  I have a little over shoulder length hair, and these are way too long.  My hair doesn't fill half of the length of the curler.  Do not use large amounts of hair in each, or you will not get defined curls.  Smaller portions work really well for defined curls. This is time consuming, so get ready to spend some time doing this.  The more you do it though, the faster you will get at it. Loading the curlers, and sectioning the hair is what takes the most time.