These curlers are more gentle for your hair than wire rollers. They are great for creating volume and lift for all hair lengths. You will enjoy experimenting with them. They come in 7 different diameters -- the narrowest diameter (1/4 inch) is for very short hair or if you want very tight curls. The medium diameters are for medium length hair. The widest diameter (7/8 inch) is for loose curls and very long hair. 6 rollers per package. All rollers are 8" long. Can be used on wet or dry hair.