Abstract: The invention relates to a coupling device for coupling a patient-side medical line to an equipment-side medical line. The device includes two parts, one fluidly coupled to each medical line. One of the parts provides both a detachable coupling that detaches when subjected to a sufficient separation force and a secure locking mechanism that requires manual separation. The detachable coupling is a breakaway connection adapted for connecting the two parts together. The secure locking mechanism provides the option of using the part to attach to corresponding secure locks of other coupling devices.