saying they can verify that the ingredients the use conform to the highest purity standards.
Hi, I can not comprehend the usage of the overstriking words, or could I say the ingredients they used?
There is apparently a typo in the sentence. I assume the second "the" should be "they" and in order to clarify, I've also added the word "that" to the part in boldface type:
They can verify the following:
The ingredients that they use conform to the highest purity standards.