What heat does the heat protection system protect up to? 21 June 2019 10:20 It protects up to 220ºC, however we do not recommend styling hair over 185ºC. Related articles Which ghd hair styling products contain heat protection? Are ghd hair products tested on animals? How do I claim on my warranty? There is a hole in my brush, what is this for? Which hair dryer can I use the ghd professional hair dryer diffuser with?