Pineapple wave bundles refer to a type of hair extension made from human hair that is designed to create a wavy hairstyle similar to the texture of a pineapple. The waves are typically loose and natural-looking, with a slight spiral pattern. Pineapple wave bundles are popular among people who want to add volume, length, and texture to their hair without using heat or chemicals. They are available in various lengths, colors, and textures, allowing for customization to match different hair types and styles.