The “Christmas tree” connector is the standard way to join two pieces of oxygen tubing: its ribbed, stepped taper wedges firmly into each tube end, sealing tighter as the tubing warms and relaxes around it. Setup: push each tubing end firmly over the ribs until snug. Listen for hissing at the joint – a soft hiss means a loose fit and lost oxygen. When to replace: replace when it discolours, cracks or no longer grips tightly. Single-patient use.





