Unique Patented Design with High Agent Capacity OES AGENA anaesthetic vaporizers are designed for use with Halothane, Enflurane, Isoflurane and Sevoflurane anaesthetic agents and are all individually calibrated and fitted with a laser engraved dial to provide high accuracy. The vaporizers have a liquid anaesthetic capacity of 400 cc greatly increasing the time between filling and therefore improving safety. Liquid level indication is provided by a flat glass indicator which clearly indicates the actual liquid level, overfill is easily identified by the large overfill portion of the sight glass. The unique wick system within the vaporiser provides consistent output throughout the flow range. The wick core incorporates the anti pumping coil aiding heat transfer at high flow rates. The temperature compensator is mounted at the front of the vaporizer in proximity to the wick thus providing additional compensation at high outputs and flow rates without compromising agent capacity.