Before extrusion, the HDPE can be pigmented to yield color-coded pipe. Common PEX tubing colors are natural (hazy clear, unpigmented), white, black, red and blue. The red and blue colors are used to help plumbers and homeowners distinguish between hot and cold water supply lines.
No, there has never been a US President from an independent party; however, at the time of his presidency, George Washington was not affiliated with a political party at all, as there were no parties in the brand new United States of America.
Grover Cleveland, the only President to ever serve nonconsecutive terms, was the 22nd and 24th President of the United States (1885-89) (1893-97). He was known to be honest, independent, and opposed to corruption and the spoils system. His motto A public office is a public trust, demonstrated his stubborn courage and integrity.