It is after much research reviews, and satisfaction on the net I find this product on amazon instead of having to order it in the US.
Otherwise, the explanation is simple (it's in French on the bottle) to understand and follow.
The first solution really dissolve the hardened thermal paste and the second (more corrosive, be careful not to leave) deep cleans well.
It is advisable to use a coffee filter to pick up, it is not easy, in the end I opted for a tissue.
A particularly avoid cotton swabs or other material that frays easily.
