Drainage system with retention ring

A drainage system comprising:

• a container having an interior and a mouth, the mouth having an outer surface and an opening;
• a frangible seal covering the opening;
• a cap secured to the mouth and in fluid communication with a drainage line, the cap having an inner surface for engaging the outer surface of the mouth, a sleeve and a widened body that is wider than the sleeve and at least partially located between the mouth and the sleeve;
• a retention ring having a distally facing surface and comprising a collar having an inner surface configured to engage an outer surface of the cap;
• a spike with a flange, the spike being configured to pierce the frangible seal in response to an initiation force being applied to the flange in a distal direction;
• a safety clip engaged with the cap and located between the flange of the spike and the retention ring, the safety clip comprising a groove member having a groove that extends partially around a distal terminal edge of the collar.