This is not a question of idiom - the sentence is just very formal legal English.
It basically means that the maker of the product does not say or guarantee that the product is suitable for any specific purpose. Not only that but the fact that they are selling the product for that purpose does not mean that it is suitable for that purpose.
It is intended to give the maker legal protection should the product not work as expected by the buyer.
I hope that helps
Student or Learner