The Q-Tube breathing circuit consists of a corrugated tube with an internally moulded panel, effectively separating the inner tubing into two halves.
Specially moulded connectors complete the circuit, allowing totally separate inspiratory and expiratory paths through the same tube.
The purpose of this is to reduce the weight and physical bulk associated with using two (2) separate tubes (inspiratory and expiratory) in lieu of a single item.

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