Patent ID: 8047210

Claim:
A hair extension comprising: an extending hair portion; and a thread connected to the extending hair portion and configured to be tied to a user's hair under attachment, wherein a ring portion is formed between both ends of the thread for inserting the user's hair, tightening, and fixing to the inserted user's hair, wherein the ring portion is formed with a first sub-ring, a first ring disposed in a direction opposite to the first sub-ring, a second sub-ring disposed in a direction opposite to the first ring, and a second ring disposed in a direction opposite to the second sub-ring obtained by folding the thread in zigzag, and forms a first ring pulling portion through a step of passing an end of the thread through the second sub-ring from one side to the other side, a step of passing through the first sub-ring from the other side to the one side after skipping the first ring, a step of passing through the first sub-ring from the other side to the one side while enclosing the exterior thread portion forming the first sub-ring and changing a direction toward the second ring, a step of passing through the second sub-ring from the one side to the other side after skipping the first ring, and a step of passing through the second ring from the other side to the one side, or formed with the first ring pulling portion, the second ring, the second sub-ring, the first ring, and the first sub-ring with steps in a reverse order, and then the first sub-ring and the second sub-ring are tightened so as to be hooked to the first ring pulling portion leaving the first ring and the second ring.