Polybutylene fittings for hot and cold water. Tubing is designed to withstand continuous operation pressures of 100 PSI at water temperatures of 180° F. Fittings allow for complete and direct transition between polybutylene, CPVC, copper, and galvanized pipe. Fittings mechanically join to any water supply tubing utilizing a special locking ring and an elastomeric seal to make quick and easy watertight connections. Tubing is flexible. “Uncopper” tubing and fittings cannot be solvent welded. Designed to adapt from metal female pipe thread to polybutylene, copper, or CPVC tubing on the cold side of a hot and cold water supply system. Carded.