How can you guarantee the testing samples are same quality as future order?

We provide 120ml free test samples for customer testing. The formula of each product is strictly adjusted, and the samples provided are directly extracted from the production line, which is consistent with the quality of the large goods. Our products are tested by high temperature, UV, packaging drop, etc. and then sold to the market. Each product is individually formulated to ensure that the quality of the sedimentation layer does not appear to be a problem.