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.
The United States was the first nation to create the office of President as the head of state in a modern republic. Current President The 45th and current President of the United States is Donald J. Trump.