The longest recorded human neck reached 40 cm in length and was created by the successive fitting of copper coils, as practiced by the women of the Padaung or Kareni tribe of Myanmar as a sign of beauty. Their necks eventually become so long and weak that they cannot support their heads without the coils. According to tribal custom, even before they reach puberty, girls must start wearing iron coils around their necks and more and more are added through the years. In some tribes the coils are removed to punish women who have committed adultery.