The cork band is a natural biodegradable product made from waste product of wine cork manufacture. The cork may stain, and we encourage you to view this as a natural patina to the product.
Do not microwave KeepCup Brew Cork Edition, it will accelerate the deterioration of the cork band by drying it out.
For longevity, we advise customers to hand wash only and to never remove the cork band, over time it will form a tight bond to the tumbler. For best results, leave the KeepCup Brew Cork Edition to dry prior to its next use.
Our cork bands are a natural product and should be treated with care, especially when fitting it to your glass. Over time, the cork band will form a tight bond with the glass.
The graphic below shows our guidance for fitting the cork band: