PEX is cross-linked polyethylene, IE PolyEthylene X-linked, not polybutylene, a different plastic.
In my neck of the woods to most people "Maintenance" equals cursing at and/or kicking something when it breaks down.
To get the degree symbol ° on Windows hold down the Alt key and type 0176 on the keyboard number pad. It is also available via the character map, and on Windows 8.1 devices with a touchscreen via the on screen keyboard.
If you are the type where the painting is more important than the frame, or you just like movies, join me in listening to the widescreen.org podcast.