4a has a visible tight cork screw pattern. It looks like an S pattern when it is stretched out. These curls are similar to 3c curls, but smaller in diameter. The circumference is often the size of a small knitting needle or crochet needle, and is prone to frizziness.
4b hair has a zig zag pattern, but no definite S pattern when stretched out. The hair strands tend to have sharp angles, and a soft cotton-like feel.
4c- hair are the tightest and most fragile curls of the pack. 4C curls have a very tightly cork screw curl pattern. The hair is extremely bouncy and springy. It shrinks up to 75% of its length. The curls do not pack densely together, but appear as individual separate strands.