Reminisce about your favourite TV show with this Friends Heat Changing Mug.

This standard sized black mug features the phrase ‘they don’t know’ until you pour in a hot drink since the mug will turn blue and says ‘they don’t know that we know they know we know.'

A versatile, durable mug that is perfect for the office or home.

Product Information:
• Heat Changing Mug
• Friends
• Design: They Don’t Know
• Material: Ceramic
• Measures: 13 x 8 x 10 cm