You must confess that if you see someone with lovely curls, you are drawn to them. Because of how unique, fun, and full of character curly hair has always been a head-turner. Compare the before and after looks of hair extensions if you don't know or can't tell the difference. If you have straight hair that requires a lot of heat and style to achieve curls, we have the greatest answer for you—even if you already have curls, refine them by adding hair extensions ranging from 3a to 3c curly hair extensions (approx. 32 in. & approx. 36 in. respectively ) Curls are defined by their thickness, which is defined by textures.