Attributes . In testing tank transport hoses from a wide variety of manufacturers, the Boss-Lock-PF fitting showed significant improvement in hose coupling retention over the conventional cam and groove shank design. Resistant to accidental disconnection when dragged. The release lever opens in the direction opposite to the cam arm, so movements that tend to open the release lever also tend to close the cam arm. Rotating action helps keep the locking device free of debris. Designed to protect critical parts from impact and to withstand rugged use. . Names