The trouble with tribbles is that they won't stop multiplying! Featuring a heat-sensitive design, this Star Trek: The Original Series Tribbles Heat Mug reveals more and more tribbles the hotter it gets. From coffee to tea, this mug makes a fun addition to your Star Trek: The Original Series collection.

• YOUR NEW FAVORITE MUG: This Star Trek: The Original Series Tribbles Heat Mug makes a gift for fans. 
• THE PERFECT GIFT: With a heat-sensitive design, this mug makes a great gift for fans of Star Trek: The Original Series. 
• SIZING: This 20 oz mug is the perfect size for your favorite morning beverage or late night brew. 
• EASY-GRIP HANDLE: This Star Trek: The Original Series mug features a large easy-grip handle for your comfort. 
• ADDITIONAL INFORMATION: Hand wash only. Do not microwave.