Colour changeable coating barrel & Bristle

During styling with hair dryer the barrel is rolled up with lots of hairs often,
then it’s extremely heated inside and outside both.
This barrel can cause people to burn their hands, hair also scalp.
To prevent this damage, here is colour changable barrel and bristels.
They help people to be aware of caution for any burn and let people wait until it’s cool down.
Moreover people can see beautiful colour changes.