PEX fittings are used to connect the flexible polyethylene pipes used in PEX water plumbing systems. Flexible PEX tubes are a low cost, problem free alternative to metal or plastic systems. You can avoid the problems of corrosion and scaling when you use a PEX system. Altogether PEX water plumbing systems are a vast improvement over older systems that use copper or rigid plastic pipes.
In cold temperatures PEX tubes retain their flexibility and do not become brittle and break. Unlike metal pipes, PEX tubing will not corrode and will not develop scales. PEX tubing is energy efficient as well because they will not conduct heat.
PEX tubing is stored on spools. Spools weigh less than metal or rigid plastic pipe making them less expensive to ship and easier to store. When used in an installation, PEX tubing can be unrolled directly from the spool and does not require coupling fittings. This saves the time and expense of running pipe. PEX tubing can be turned 90 degrees eliminating the need for elbow fittings. PEX tubing does not need to be soldered so there are no unhealthy fumes and dangers posed by using a torch.