Flash Furs/Skull Trophies/Toof Necklace

From Lexicanum

Flash Furs, Skull Trophies and Toof Necklaces all have similar effects, enhancing the already prestigious standing of a Nob or Warboss. They are parts of the most powerful creatures a hunta has killed and the parts are worn as a sign of his skill and ruthlessness in combat. Skulls are often hung from a stick above the boss and teeth will usually be worn like a pendant around the neck.

Sources

• Feral Ork Army List