2N to be honest, it's really good. I suggest massage with essential oil, apply 2N stovepipe cream to perm, and sometimes even sweat on your legs. However, it is recommended to wear disposable gloves when applying, otherwise your fingers will be very hot and uncomfortable. Whether it works or not, just keep warm in winter. Ha ha.

If the landlord feels too hot after using it, he can put some alcohol on his legs, which will absorb heat, and it seems that it will not affect the effect.