Describe the viscosity of a product used for permanent waving.

The viscosity of a product used for permanent waving is classified as thick. Thick formulations are crucial for ensuring that the perm solution adheres properly to the hair strands and penetrates effectively. A thicker consistency allows for better control during application, helping to prevent the product from dripping and ensuring even distribution throughout the hair. This is particularly important during the waving process, as it helps to achieve the desired curl pattern and longevity of the wave.

In contrast, thinner or runnier products may not provide the same level of coverage or control, potentially leading to inconsistent results. Medium viscosity also does not offer the dense consistency necessary for effective chemical processing involved in permanent waving. The thick texture of a perm solution contributes significantly to its ability to alter the hair's structure, making it a vital characteristic of the product.