Hello Duanes,
We're sorry to hear that you have some frustrations with your Cantara faucet. The supply lines are made out of a material called PERT, which is a form of engineering plastic, and very are common in the plumbing industry. Many new homes are implementing these types of lines, in place of copper lines, because they last longer and are more durable. If you have any further questions about your faucet, or if there is anything more we can do to improve your Pfister experience, please do not hesitate to contact our customer support team at 1-800-PFAUCET (1-800-732-8238).
Thank you for your review, Pfister