QESTPEX: A practical hot/cold pressure plumbing system for every kind of job. This system was developed to meet the needs of plumbing professionals and is extremely efficient. The tubing is flexible at all temperatures and can be installed in long lengths with minimal use of joints and elbows. Other advantages include: Corrosion resistant ~ Freeze damage tolerant ~ No exotic parts to fail ~ No solvents ~ Quicker, easier connections ~ Low heat conductivity ~ Elimination of most water hammer conditions. PEX can handle all normal temperatures and pressures for residential portable water systems. Easier to lay out and rough in both winter and summer. PEX is resistant to mineral build up, rust and electrolysis. The piping can be connected to galvanized, copper, polybutylene, and CPVC systems with the standard fittings. PEX should not be used in the following instances: Where exposed to or stored in direct sunlight ~ In continuously circulating hot water plumbing loops ~ Air conditioning systems with refrigerant.