Weave hair extensions Weave hair extensions are one type of hair extensions for long-term use. Like other types of hair extensions, weave hair extensions are designed to make one’s hair appear thicker or longer. This type of hair extensions comes in a variety of colors, lengths, and textures. They are available in straight, wavy, curly or other textures, and the length generally ranges from 14 inch to 32 inch. The extensions are made from human hair or synthetic fiber hair. Human hair extensions can be cut, straightened, dyed, curled, or treated like real hair, while synthetic fiber hair is difficult to get dyed, and it can not be curled and straightened because the heat in curling and straightening may melt the strands.