Star Trek Tribble, Gray - New Dual Sound Version! - Medium Size New Dual Sound Version with BOTH Cooing AND Agitated Sounds! The Softest Electronic Tribbles Ever Made - features the Both Original Sound FX from the Classic Star Trek episode, "The Trouble with Tribbles" Medium Size Tribbles are 5" x 4.5 x 4" Sound and Vibrating FX activated by Touch - Pet or Tap it gently and The Tribble will come to Life! Hidden Velcro Pouch Safely Hides Electronics