Condensation or "rain-out" is a problem in medical circuits and previous attempts to manage and/or prevent rain-out have resulted in relatively expensive and/or difficult to manufacture medical circuit components. The subject patent provides an improved medical circuit component for managing rain-out. In particular the component may be an improved breathing tube, or insufflation system limb comprising a helically corrugated tube (1) preferably incorporating a heater wire (2, 7).